Usando o controle ASP.NET UpdatePanel com controles associado a dados
Você pode criar uma experiência de usuário mais rica em seus aplicativos ASP.NET com habilitado AJAX usando renderização parcial da página.A renderização parcial da página remove a necessidade de a página toda ser atualizada como o resultado de um postback.Em vez disso, você pode especificar apenas a região da página a ser atualizada.Como resultado, os usuários não veem a página inteira recarregar com cada postback.
Este tópico pressupõe que você é familiarizado com o controle UpdatePanel.Caso contrário, revise os seguintes tópicos:
Você pode habilitar renderização parcial da página usando controles de servidor Web UpdatePanel e ScriptManager.O controle UpdatePanel identifica uma região de uma página que pode ser atualizada.O controle ScriptManager mantém registro dos controles UpdatePanel que estão em uma página e os controles que disparam os controles UpdatePanel para atualizar.Os controles dentro de um controle UpdatePanel que causam um postback automaticamente são identificados como disparadores para o painel de atualização.Você também pode especificar controles que são controles fora de um controle UpdatePanel.Disparadores externos podem ser controles filho de outro controle UpdatePanel.Para obter mais informações, consulte Visão geral de renderização de página parcial e Visão geral sobre controle UpdatePanel.
Este tópico contém as seções a seguir:
Usando vários controles UpdatePanel em uma página
Desativação de disparadores automáticos
Gerenciando disparadores e atualizando um UpdatePanel de forma programática
Ativar renderização parcial da página em um controle personalizado
Usando vários controles UpdatePanel em uma página
Não há um limite para o número de controles UpdatePanel que você pode colocar em uma página.Como resultado, você pode especificar regiões de uma página que são atualizadas independentemente da página inteira e independentemente uns dos outros.
Por padrão, a propriedade UpdateMode de um controle UpdatePanel é definida como Always.Isso significa que sempre que uma atualização parcial de página é disparada, o controle UpdatePanel atualiza a página, mesmo se o disparador foi não para o controle UpdatePanel.Para certificar-se que o controle UpdatePanel seja atualizado somente quando ele foi acionado, você pode definir a propriedade UpdateMode do controle UpdatePanelConditional.
O exemplo a seguir inclue dois controles UpdatePanel.Um controle inclui controles da Web que aceitam entrada do usuário, e o outro controle exibe o que o usuário insere.Cada controle UpdatePanel tem sua propriedade UpdateMode definida como Conditional. como um resultado, se um usuário clica no botão Cancel para limpar os campos do formulário de entrada, apenas o formulário de entrada do controle UpdatePanel é atualizado.Se um usuário clicar no botão Insert para enviar o formulário, os dois controles UpdatePanel são atualizados.
<%@ Page Language="VB" %>
<%@ Import Namespace="System.Collections.Generic" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" >
<title>Enter New Employees</title>
<script >
Private EmployeeList As List(Of Employee)
Protected Sub Page_Load()
If Not IsPostBack Then
EmployeeList = New List(Of Employee)
EmployeeList.Add(New Employee(1, "Jump", "Dan"))
EmployeeList.Add(New Employee(2, "Kirwan", "Yvette"))
ViewState("EmployeeList") = EmployeeList
Else
EmployeeList = CType(ViewState("EmployeeList"), List(Of Employee))
End If
EmployeesGridView.DataSource = EmployeeList
EmployeesGridView.DataBind()
End Sub
Protected Sub InsertButton_Click(ByVal sender As Object, ByVal e As EventArgs)
If String.IsNullOrEmpty(FirstNameTextBox.Text) Or _
String.IsNullOrEmpty(LastNameTextBox.Text) Then Return
Dim employeeID As Integer = EmployeeList(EmployeeList.Count - 1).EmployeeID + 1
Dim lastName As String = Server.HtmlEncode(FirstNameTextBox.Text)
Dim firstName As String = Server.HtmlEncode(LastNameTextBox.Text)
FirstNameTextBox.Text = String.Empty
LastNameTextBox.Text = String.Empty
EmployeeList.Add(New Employee(employeeID, lastName, firstName))
ViewState("EmployeeList") = EmployeeList
EmployeesGridView.DataBind()
EmployeesGridView.PageIndex = EmployeesGridView.PageCount
End Sub
Protected Sub CancelButton_Click(ByVal sender As Object, ByVal e As EventArgs)
FirstNameTextBox.Text = String.Empty
LastNameTextBox.Text = String.Empty
End Sub
<Serializable()> _
Public Class Employee
Private _employeeID As Integer
Private _lastName As String
Private _firstName As String
Public ReadOnly Property EmployeeID() As Integer
Get
Return _employeeID
End Get
End Property
Public ReadOnly Property LastName() As String
Get
Return _lastName
End Get
End Property
Public ReadOnly Property FirstName() As String
Get
Return _firstName
End Get
End Property
Public Sub New(ByVal employeeID As Integer, ByVal lastName As String, ByVal firstName As String)
_employeeID = employeeID
_lastName = lastName
_firstName = firstName
End Sub
End Class
</script>
</head>
<body>
<form id="form1" >
<div>
</div>
<asp:ScriptManager ID="ScriptManager1" EnablePartialRendering="true" />
<table>
<tr>
<td style="height: 206px" valign="top">
<asp:UpdatePanel ID="InsertEmployeeUpdatePanel" UpdateMode="Conditional">
<ContentTemplate>
<table cellpadding="2" border="0" style="background-color:#7C6F57">
<tr>
<td><asp:Label ID="FirstNameLabel" AssociatedControlID="FirstNameTextBox"
Text="First Name" ForeColor="White" /></td>
<td><asp:TextBox ID="FirstNameTextBox" /></td>
</tr>
<tr>
<td><asp:Label ID="LastNameLabel" AssociatedControlID="LastNameTextBox"
Text="Last Name" ForeColor="White" /></td>
<td><asp:TextBox ID="LastNameTextBox" /></td>
</tr>
<tr>
<td></td>
<td>
<asp:LinkButton ID="InsertButton" Text="Insert" OnClick="InsertButton_Click" ForeColor="White" />
<asp:LinkButton ID="Cancelbutton" Text="Cancel" OnClick="CancelButton_Click" ForeColor="White" />
</td>
</tr>
</table>
<asp:Label ID="InputTimeLabel"><%=DateTime.Now %></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
</td>
<td style="height: 206px" valign="top">
<asp:UpdatePanel ID="EmployeesUpdatePanel" UpdateMode="Conditional">
<ContentTemplate>
<asp:GridView ID="EmployeesGridView" BackColor="LightGoldenrodYellow" BorderColor="Tan"
BorderWidth="1px" CellPadding="2" ForeColor="Black" GridLines="None" AutoGenerateColumns="False">
<FooterStyle BackColor="Tan" />
<SelectedRowStyle BackColor="DarkSlateBlue" ForeColor="GhostWhite" />
<PagerStyle BackColor="PaleGoldenrod" ForeColor="DarkSlateBlue" HorizontalAlign="Center" />
<HeaderStyle BackColor="Tan" Font-Bold="True" />
<AlternatingRowStyle BackColor="PaleGoldenrod" />
<Columns>
<asp:BoundField DataField="EmployeeID" HeaderText="Employee ID" />
<asp:BoundField DataField="LastName" HeaderText="Last Name" />
<asp:BoundField DataField="FirstName" HeaderText="First Name" />
</Columns>
<PagerSettings PageButtonCount="5" />
</asp:GridView>
<asp:Label ID="ListTimeLabel"><%=DateTime.Now %></asp:Label>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="InsertButton" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
</td>
</tr>
</table>
</form>
</body>
</html>
<%@ Page Language="C#" %>
<%@ Import Namespace="System.Collections.Generic" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head >
<title>Enter New Employees</title>
<script >
private List<Employee> EmployeeList;
protected void Page_Load()
{
if (!IsPostBack)
{
EmployeeList = new List<Employee>();
EmployeeList.Add(new Employee(1, "Jump", "Dan"));
EmployeeList.Add(new Employee(2, "Kirwan", "Yvette"));
ViewState["EmployeeList"] = EmployeeList;
}
else
EmployeeList = (List<Employee>)ViewState["EmployeeList"];
EmployeesGridView.DataSource = EmployeeList;
EmployeesGridView.DataBind();
}
protected void InsertButton_Click(object sender, EventArgs e)
{
if (String.IsNullOrEmpty(FirstNameTextBox.Text) ||
String.IsNullOrEmpty(LastNameTextBox.Text)) { return; }
int employeeID = EmployeeList[EmployeeList.Count-1].EmployeeID + 1;
string lastName = Server.HtmlEncode(FirstNameTextBox.Text);
string firstName = Server.HtmlEncode(LastNameTextBox.Text);
FirstNameTextBox.Text = String.Empty;
LastNameTextBox.Text = String.Empty;
EmployeeList.Add(new Employee(employeeID, lastName, firstName));
ViewState["EmployeeList"] = EmployeeList;
EmployeesGridView.DataBind();
EmployeesGridView.PageIndex = EmployeesGridView.PageCount;
}
protected void CancelButton_Click(object sender, EventArgs e)
{
FirstNameTextBox.Text = String.Empty;
LastNameTextBox.Text = String.Empty;
}
[Serializable]
public class Employee
{
private int _employeeID;
private string _lastName;
private string _firstName;
public int EmployeeID
{
get { return _employeeID; }
}
public string LastName
{
get { return _lastName; }
}
public string FirstName
{
get { return _firstName; }
}
public Employee(int employeeID, string lastName, string firstName)
{
_employeeID = employeeID;
_lastName = lastName;
_firstName = firstName;
}
}
</script>
</head>
<body>
<form id="form1" >
<div>
</div>
<asp:ScriptManager ID="ScriptManager1" EnablePartialRendering="true" />
<table>
<tr>
<td style="height: 206px" valign="top">
<asp:UpdatePanel ID="InsertEmployeeUpdatePanel" UpdateMode="Conditional">
<ContentTemplate>
<table cellpadding="2" border="0" style="background-color:#7C6F57">
<tr>
<td><asp:Label ID="FirstNameLabel" AssociatedControlID="FirstNameTextBox"
Text="First Name" ForeColor="White" /></td>
<td><asp:TextBox ID="FirstNameTextBox" /></td>
</tr>
<tr>
<td><asp:Label ID="LastNameLabel" AssociatedControlID="LastNameTextBox"
Text="Last Name" ForeColor="White" /></td>
<td><asp:TextBox ID="LastNameTextBox" /></td>
</tr>
<tr>
<td></td>
<td>
<asp:LinkButton ID="InsertButton" Text="Insert" OnClick="InsertButton_Click" ForeColor="White" />
<asp:LinkButton ID="Cancelbutton" Text="Cancel" OnClick="CancelButton_Click" ForeColor="White" />
</td>
</tr>
</table>
<asp:Label ID="InputTimeLabel"><%=DateTime.Now %></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
</td>
<td style="height: 206px" valign="top">
<asp:UpdatePanel ID="EmployeesUpdatePanel" UpdateMode="Conditional">
<ContentTemplate>
<asp:GridView ID="EmployeesGridView" BackColor="LightGoldenrodYellow" BorderColor="Tan"
BorderWidth="1px" CellPadding="2" ForeColor="Black" GridLines="None" AutoGenerateColumns="False">
<FooterStyle BackColor="Tan" />
<SelectedRowStyle BackColor="DarkSlateBlue" ForeColor="GhostWhite" />
<PagerStyle BackColor="PaleGoldenrod" ForeColor="DarkSlateBlue" HorizontalAlign="Center" />
<HeaderStyle BackColor="Tan" Font-Bold="True" />
<AlternatingRowStyle BackColor="PaleGoldenrod" />
<Columns>
<asp:BoundField DataField="EmployeeID" HeaderText="Employee ID" />
<asp:BoundField DataField="LastName" HeaderText="Last Name" />
<asp:BoundField DataField="FirstName" HeaderText="First Name" />
</Columns>
<PagerSettings PageButtonCount="5" />
</asp:GridView>
<asp:Label ID="ListTimeLabel"><%=DateTime.Now %></asp:Label>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="InsertButton" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
</td>
</tr>
</table>
</form>
</body>
</html>
Você também pode aninhar um UpdatePanel controle dentro de outro controle UpdatePanel.Se você definir a propriedade UpdateMode dos controles externos e aninhados para Conditional, o painel externo não é atualizado quando somente o painel interno é disparado.No entanto, se um disparador atualiza o painel externo, os painéis externos e internos são atualizados.
O exemplo a seguir inclui um controle GridView dentro de um controle UpdatePanel.Cada linha do controle GridView contém um controle GridView aninhado que está dentro de um controle filho UpdatePanel.Quando um controle GridView interno exibe uma nova página de registros, o painel externo e os painéis nas outras linhas do controle GridView externo não são atualizados.Quando o controle GridView externo exibe uma nova página de registros, o painel externo e os painéis aninhados são todos atualizados.
<%@ Page Language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head >
<title>Browse Departments</title>
<script >
Protected Sub DepartmentsGridView_RowDataBound(sender As object, e As GridViewRowEventArgs)
If e.Row.RowType = DataControlRowType.DataRow Then
Dim s As SqlDataSource = CType(e.Row.FindControl("EmployeesDataSource"), SqlDataSource)
Dim r As System.Data.DataRowView = CType(e.Row.DataItem, System.Data.DataRowView)
s.SelectParameters("DepartmentID").DefaultValue = r("DepartmentID").ToString()
End If
End Sub
</script>
</head>
<body>
<form id="form1" >
<div>
<asp:ScriptManager ID="ScriptManager1" EnablePartialRendering="true" />
<asp:UpdatePanel ID="UpdatePanel2" UpdateMode="Conditional">
<ContentTemplate>
<asp:GridView ID="DepartmentsGridView" AllowPaging="True" AllowSorting="True"
AutoGenerateColumns="False" CellPadding="4" DataSourceID="DepartmentDataSource"
ForeColor="#333333" GridLines="None" PageSize="3" OnRowDataBound="DepartmentsGridView_RowDataBound">
<FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
<Columns>
<asp:BoundField DataField="GroupName" HeaderText="Division" SortExpression="GroupName" >
<ItemStyle Width="200px" />
</asp:BoundField>
<asp:BoundField DataField="Name" HeaderText="Department Name" SortExpression="Name" >
<ItemStyle Width="160px" />
</asp:BoundField>
<asp:TemplateField HeaderText="Employees">
<ItemTemplate>
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional">
<ContentTemplate>
<asp:GridView ID="EmployeesGridView" AllowPaging="True" AllowSorting="True"
AutoGenerateColumns="False" BackColor="White" BorderColor="#999999" BorderStyle="None"
BorderWidth="1px" CellPadding="3" DataSourceID="EmployeesDataSource" GridLines="Vertical"
PageSize="4">
<FooterStyle BackColor="#CCCCCC" ForeColor="Black" />
<Columns>
<asp:BoundField DataField="FirstName" HeaderText="First Name" SortExpression="FirstName" >
<ItemStyle Width="80px" />
</asp:BoundField>
<asp:BoundField DataField="LastName" HeaderText="Last Name" SortExpression="LastName" >
<ItemStyle Width="160px" />
</asp:BoundField>
</Columns>
<RowStyle BackColor="#EEEEEE" ForeColor="Black" />
<SelectedRowStyle BackColor="#008A8C" Font-Bold="True" ForeColor="White" />
<PagerStyle BackColor="#999999" ForeColor="Black" HorizontalAlign="Center" />
<HeaderStyle BackColor="#000084" Font-Bold="True" ForeColor="White" />
<AlternatingRowStyle BackColor="Gainsboro" />
</asp:GridView>
<asp:Label ID="InnerTimeLabel"><%=DateTime.Now %></asp:Label>
<asp:SqlDataSource ID="EmployeesDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT HumanResources.EmployeeDepartmentHistory.DepartmentID,
HumanResources.vEmployee.EmployeeID,
HumanResources.vEmployee.FirstName,
HumanResources.vEmployee.LastName
FROM HumanResources.EmployeeDepartmentHistory
INNER JOIN HumanResources.vEmployee
ON HumanResources.EmployeeDepartmentHistory.EmployeeID = HumanResources.vEmployee.EmployeeID
WHERE HumanResources.EmployeeDepartmentHistory.DepartmentID = @DepartmentID
ORDER BY HumanResources.vEmployee.LastName ASC, HumanResources.vEmployee.FirstName ASC">
<SelectParameters>
<asp:Parameter Name="DepartmentID" DefaultValue="0" Type="int32" />
</SelectParameters>
</asp:SqlDataSource>
</ContentTemplate>
</asp:UpdatePanel>
</ItemTemplate>
<ItemStyle Height="170px" Width="260px" />
</asp:TemplateField>
</Columns>
<RowStyle BackColor="#F7F6F3" ForeColor="#333333" VerticalAlign="Top" />
<EditRowStyle BackColor="#999999" />
<SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
<PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
<HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" HorizontalAlign="Left" />
<AlternatingRowStyle BackColor="White" ForeColor="#284775" VerticalAlign="Top" />
</asp:GridView>
<asp:Label ID="OuterTimeLabel"><%=DateTime.Now %></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
<asp:SqlDataSource ID="DepartmentDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT DepartmentID, Name, GroupName FROM HumanResources.Department ORDER BY Name">
</asp:SqlDataSource>
</div>
</form>
</body>
</html>
<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head >
<title>Browse Departments</title>
<script >
protected void DepartmentsGridView_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
SqlDataSource s = (SqlDataSource)e.Row.FindControl("EmployeesDataSource");
System.Data.DataRowView r = (System.Data.DataRowView)e.Row.DataItem;
s.SelectParameters["DepartmentID"].DefaultValue = r["DepartmentID"].ToString();
}
}
</script>
</head>
<body>
<form id="form1" >
<div>
<asp:ScriptManager ID="ScriptManager1" EnablePartialRendering="true" />
<asp:UpdatePanel ID="UpdatePanel2" UpdateMode="Conditional">
<ContentTemplate>
<asp:GridView ID="DepartmentsGridView" AllowPaging="True" AllowSorting="True"
AutoGenerateColumns="False" CellPadding="4" DataSourceID="DepartmentDataSource"
ForeColor="#333333" GridLines="None" PageSize="3" OnRowDataBound="DepartmentsGridView_RowDataBound">
<FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
<Columns>
<asp:BoundField DataField="GroupName" HeaderText="Division" SortExpression="GroupName" >
<ItemStyle Width="200px" />
</asp:BoundField>
<asp:BoundField DataField="Name" HeaderText="Department Name" SortExpression="Name" >
<ItemStyle Width="160px" />
</asp:BoundField>
<asp:TemplateField HeaderText="Employees">
<ItemTemplate>
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional">
<ContentTemplate>
<asp:GridView ID="EmployeesGridView" AllowPaging="True" AllowSorting="True"
AutoGenerateColumns="False" BackColor="White" BorderColor="#999999" BorderStyle="None"
BorderWidth="1px" CellPadding="3" DataSourceID="EmployeesDataSource" GridLines="Vertical"
PageSize="4">
<FooterStyle BackColor="#CCCCCC" ForeColor="Black" />
<Columns>
<asp:BoundField DataField="FirstName" HeaderText="First Name" SortExpression="FirstName" >
<ItemStyle Width="80px" />
</asp:BoundField>
<asp:BoundField DataField="LastName" HeaderText="Last Name" SortExpression="LastName" >
<ItemStyle Width="160px" />
</asp:BoundField>
</Columns>
<RowStyle BackColor="#EEEEEE" ForeColor="Black" />
<SelectedRowStyle BackColor="#008A8C" Font-Bold="True" ForeColor="White" />
<PagerStyle BackColor="#999999" ForeColor="Black" HorizontalAlign="Center" />
<HeaderStyle BackColor="#000084" Font-Bold="True" ForeColor="White" />
<AlternatingRowStyle BackColor="Gainsboro" />
</asp:GridView>
<asp:Label ID="InnerTimeLabel"><%=DateTime.Now %></asp:Label>
<asp:SqlDataSource ID="EmployeesDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT HumanResources.EmployeeDepartmentHistory.DepartmentID,
HumanResources.vEmployee.EmployeeID,
HumanResources.vEmployee.FirstName,
HumanResources.vEmployee.LastName
FROM HumanResources.EmployeeDepartmentHistory
INNER JOIN HumanResources.vEmployee
ON HumanResources.EmployeeDepartmentHistory.EmployeeID = HumanResources.vEmployee.EmployeeID
WHERE HumanResources.EmployeeDepartmentHistory.DepartmentID = @DepartmentID
ORDER BY HumanResources.vEmployee.LastName ASC, HumanResources.vEmployee.FirstName ASC">
<SelectParameters>
<asp:Parameter Name="DepartmentID" DefaultValue="0" Type="int32" />
</SelectParameters>
</asp:SqlDataSource>
</ContentTemplate>
</asp:UpdatePanel>
</ItemTemplate>
<ItemStyle Height="170px" Width="260px" />
</asp:TemplateField>
</Columns>
<RowStyle BackColor="#F7F6F3" ForeColor="#333333" VerticalAlign="Top" />
<EditRowStyle BackColor="#999999" />
<SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
<PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
<HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" HorizontalAlign="Left" />
<AlternatingRowStyle BackColor="White" ForeColor="#284775" VerticalAlign="Top" />
</asp:GridView>
<asp:Label ID="OuterTimeLabel"><%=DateTime.Now %></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
<asp:SqlDataSource ID="DepartmentDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT DepartmentID, Name, GroupName FROM HumanResources.Department ORDER BY Name">
</asp:SqlDataSource>
</div>
</form>
</body>
</html>
Desativação de disparadores automáticos
Os controles dentro de um controle UpdatePanel que causam um postback são configurados automaticamente como disparadores para este controle UpdatePanel.No entanto, convém desabilitar os disparadores automáticos e acionar uma atualização do controle UpdatePanel a aprtir de apenas um controle externo.Para fazer isto, defina a propriedade ChildrenAsTriggers do controle UpdatePanel para false.Em seguida, configure a propriedade UpdateMode do controle UpdatePanel para Conditional.Essas definições de propriedade farão com que uma atualização do painel seja causada somente se disparado um controle externo ou por uma chamada para o método Update.
O exemplo a seguir exibe as categorias, subcategorias e nomes de produtos a partir de banco de dados de exemplo AdventureWorks.A lista de categorias raramente se altera e não é necessário atualizar a lista de categorias cada vez que é exibida uma lista de produtos ou subcategorias.Portanto, no controle UpdatePanel que contém a lista de categoria, você pode definir a propriedade ChildrenAsTriggersfalse e a propriedade UpdateMode para Conditional.Isso garante que o controle UpdatePanel atualize apenas quando explicitamente solicitado.
<%@ Page Language="VB" AutoEventWireup="true" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head >
<title>UpdatePanel Example</title>
<script >
Protected Sub ProductsUpdatePanel_Load(sender As Object, e As EventArgs)
CategoryTimeLabel.Text = DateTime.Now.ToString()
End Sub
Protected Sub CategoriesRepeater_ItemCommand(sender As Object, e As RepeaterCommandEventArgs)
SubcategoriesDataSource.SelectParameters("CategoryID").DefaultValue = e.CommandArgument.ToString()
SubcategoriesRepeater.DataBind()
ProductsDataSource.SelectParameters("SubcategoryID").DefaultValue = "0"
ProductsGridView.DataBind()
End Sub
Protected Sub SubcategoriesRepeater_ItemCommand(sender As Object, e As RepeaterCommandEventArgs)
ProductsDataSource.SelectParameters("SubcategoryID").DefaultValue = e.CommandArgument.ToString()
ProductsGridView.DataBind()
End Sub
Protected Sub RefreshCategoriesButton_Click(sender As Object, e As EventArgs)
SubcategoriesDataSource.SelectParameters("CategoryID").DefaultValue = "0"
SubcategoriesRepeater.DataBind()
ProductsDataSource.SelectParameters("SubcategoryID").DefaultValue = "0"
ProductsGridView.DataBind()
End Sub
</script>
</head>
<body>
<form id="form1" >
<div>
<asp:ScriptManager ID="ScriptManager1" >
</asp:ScriptManager>
<table>
<tr>
<td valign="top" style="width:120px">
<asp:UpdatePanel ID="ProductsUpdatePanel"
ChildrenAsTriggers="False"
OnLoad="ProductsUpdatePanel_Load" UpdateMode="Conditional">
<ContentTemplate>
<asp:Repeater ID="CategoryRepeater" DataSourceID="CategoriesDataSource"
OnItemCommand="CategoriesRepeater_ItemCommand">
<ItemTemplate>
<asp:LinkButton ID="SelectCategoryButton"
Text='<%# Eval("Name") %>'
CommandName="SelectCategory"
CommandArgument='<%#Eval("ProductCategoryID") %>' /><br />
</ItemTemplate>
</asp:Repeater>
<asp:SqlDataSource ID="CategoriesDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT Name, ProductCategoryID FROM Production.ProductCategory ORDER BY ProductCategoryID">
</asp:SqlDataSource>
<br />
<asp:Label ID="CategoryTimeLabel" Text="Label" Font-Size="Smaller"></asp:Label>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="RefreshCategoriesButton" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
<asp:LinkButton runat="Server" ID="RefreshCategoriesButton" Text="Refresh Category List"
OnClick="RefreshCategoriesButton_Click" Font-Size="smaller" />
</td>
<td valign="top">
<asp:UpdatePanel ID="SubcategoriesUpdatePanel" >
<ContentTemplate>
<asp:Repeater ID="SubcategoriesRepeater" DataSourceID="SubcategoriesDataSource"
OnItemCommand="SubcategoriesRepeater_ItemCommand" >
<ItemTemplate>
<asp:LinkButton ID="SelectSubcategoryButton"
Text='<%# Eval("Name") %>'
CommandName="SelectSubcategory"
CommandArgument='<%#Eval("ProductSubcategoryID") %>' /><br />
</ItemTemplate>
</asp:Repeater>
<asp:SqlDataSource ID="SubcategoriesDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT Name, ProductSubcategoryID FROM Production.ProductSubcategory
WHERE Production.ProductSubcategory.ProductCategoryID = @CategoryID
ORDER BY Name">
<SelectParameters>
<asp:Parameter Name="CategoryID" DefaultValue="0" />
</SelectParameters>
</asp:SqlDataSource>
</ContentTemplate>
</asp:UpdatePanel>
</td>
<td valign="top">
<asp:UpdatePanel ID="ProductUpdatePanel" >
<ContentTemplate>
<asp:GridView ID="ProductsGridView" AllowPaging="True" AutoGenerateColumns="False" BackColor="White" BorderColor="#E7E7FF" BorderStyle="None" BorderWidth="1px" CellPadding="3" DataKeyNames="ProductID" DataSourceID="ProductsDataSource" GridLines="Horizontal">
<FooterStyle BackColor="#B5C7DE" ForeColor="#4A3C8C" />
<Columns>
<asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name" >
<ItemStyle Width="240px" />
</asp:BoundField>
</Columns>
<RowStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" />
<SelectedRowStyle BackColor="#738A9C" Font-Bold="True" ForeColor="#F7F7F7" />
<PagerStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" HorizontalAlign="Right" />
<HeaderStyle BackColor="#4A3C8C" Font-Bold="True" ForeColor="#F7F7F7" />
<AlternatingRowStyle BackColor="#F7F7F7" />
</asp:GridView>
<asp:SqlDataSource ID="ProductsDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT ProductID, Name, ProductSubcategoryID FROM Production.Product WHERE (ProductSubcategoryID = @SubcategoryID) ORDER BY Name">
<SelectParameters>
<asp:Parameter DefaultValue="0" Name="SubcategoryID" />
</SelectParameters>
</asp:SqlDataSource>
</ContentTemplate>
</asp:UpdatePanel>
</td>
</tr>
</table>
</div>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="true" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head >
<title>UpdatePanel Example</title>
<script >
protected void ProductsUpdatePanel_Load(object sender, EventArgs e)
{
CategoryTimeLabel.Text = DateTime.Now.ToString();
}
protected void CategoriesRepeater_ItemCommand(object sender, RepeaterCommandEventArgs e)
{
SubcategoriesDataSource.SelectParameters["CategoryID"].DefaultValue = e.CommandArgument.ToString();
SubcategoriesRepeater.DataBind();
ProductsDataSource.SelectParameters["SubcategoryID"].DefaultValue = "0";
ProductsGridView.DataBind();
}
protected void SubcategoriesRepeater_ItemCommand(object sender, RepeaterCommandEventArgs e)
{
ProductsDataSource.SelectParameters["SubcategoryID"].DefaultValue = e.CommandArgument.ToString();
ProductsGridView.DataBind();
}
protected void RefreshCategoriesButton_Click(object sender, EventArgs e)
{
SubcategoriesDataSource.SelectParameters["CategoryID"].DefaultValue = "0";
SubcategoriesRepeater.DataBind();
ProductsDataSource.SelectParameters["SubcategoryID"].DefaultValue = "0";
ProductsGridView.DataBind();
}
</script>
</head>
<body>
<form id="form1" >
<div>
<asp:ScriptManager ID="ScriptManager1" >
</asp:ScriptManager>
<table>
<tr>
<td valign="top" style="width:120px">
<asp:UpdatePanel ID="ProductsUpdatePanel"
ChildrenAsTriggers="False"
OnLoad="ProductsUpdatePanel_Load" UpdateMode="Conditional">
<ContentTemplate>
<asp:Repeater ID="CategoryRepeater" DataSourceID="CategoriesDataSource"
OnItemCommand="CategoriesRepeater_ItemCommand">
<ItemTemplate>
<asp:LinkButton ID="SelectCategoryButton"
Text='<%# Eval("Name") %>'
CommandName="SelectCategory"
CommandArgument='<%#Eval("ProductCategoryID") %>' /><br />
</ItemTemplate>
</asp:Repeater>
<asp:SqlDataSource ID="CategoriesDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT Name, ProductCategoryID FROM Production.ProductCategory ORDER BY ProductCategoryID">
</asp:SqlDataSource>
<br />
<asp:Label ID="CategoryTimeLabel" Text="Label" Font-Size="Smaller"></asp:Label>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="RefreshCategoriesButton" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
<asp:LinkButton runat="Server" ID="RefreshCategoriesButton" Text="Refresh Category List"
OnClick="RefreshCategoriesButton_Click" Font-Size="smaller" />
</td>
<td valign="top">
<asp:UpdatePanel ID="SubcategoriesUpdatePanel" >
<ContentTemplate>
<asp:Repeater ID="SubcategoriesRepeater" DataSourceID="SubcategoriesDataSource"
OnItemCommand="SubcategoriesRepeater_ItemCommand" >
<ItemTemplate>
<asp:LinkButton ID="SelectSubcategoryButton"
Text='<%# Eval("Name") %>'
CommandName="SelectSubcategory"
CommandArgument='<%#Eval("ProductSubcategoryID") %>' /><br />
</ItemTemplate>
</asp:Repeater>
<asp:SqlDataSource ID="SubcategoriesDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT Name, ProductSubcategoryID FROM Production.ProductSubcategory
WHERE Production.ProductSubcategory.ProductCategoryID = @CategoryID
ORDER BY Name">
<SelectParameters>
<asp:Parameter Name="CategoryID" DefaultValue="0" />
</SelectParameters>
</asp:SqlDataSource>
</ContentTemplate>
</asp:UpdatePanel>
</td>
<td valign="top">
<asp:UpdatePanel ID="ProductUpdatePanel" >
<ContentTemplate>
<asp:GridView ID="ProductsGridView" AllowPaging="True" AutoGenerateColumns="False" BackColor="White" BorderColor="#E7E7FF" BorderStyle="None" BorderWidth="1px" CellPadding="3" DataKeyNames="ProductID" DataSourceID="ProductsDataSource" GridLines="Horizontal">
<FooterStyle BackColor="#B5C7DE" ForeColor="#4A3C8C" />
<Columns>
<asp:BoundField DataField="Name" HeaderText="Name" SortExpression="Name" >
<ItemStyle Width="240px" />
</asp:BoundField>
</Columns>
<RowStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" />
<SelectedRowStyle BackColor="#738A9C" Font-Bold="True" ForeColor="#F7F7F7" />
<PagerStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" HorizontalAlign="Right" />
<HeaderStyle BackColor="#4A3C8C" Font-Bold="True" ForeColor="#F7F7F7" />
<AlternatingRowStyle BackColor="#F7F7F7" />
</asp:GridView>
<asp:SqlDataSource ID="ProductsDataSource" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT ProductID, Name, ProductSubcategoryID FROM Production.Product WHERE (ProductSubcategoryID = @SubcategoryID) ORDER BY Name">
<SelectParameters>
<asp:Parameter DefaultValue="0" Name="SubcategoryID" />
</SelectParameters>
</asp:SqlDataSource>
</ContentTemplate>
</asp:UpdatePanel>
</td>
</tr>
</table>
</div>
</form>
</body>
</html>
Gerenciando disparadores e atualizando um UpdatePanel de forma programática
Controles que disparam um controle UpdatePanel de atualização devem ser registrados com o controle ScriptManager na página.Isso ocorre automaticamente para os controles filho em um controle UpdatePanel.Você pode especificar disparadores declarativamente usando a coleção Triggers de um controle UpdatePanel.Além disso, você pode programaticamente identificar disparadores e usar código do servidor para fazer com que um controle UpdatePanel seja atualizado.
Em casos onde um controle de disparador não está disponível em tempo de design, você pode registrar o controle como um disparador, usando o método RegisterAsyncPostBackControl do controle ScriptManager.Controles que são identificados por meio de programação como disparadores devem ser registrados toda vez que ocorre um postback.Recomendamos que você coloque chamadas para o método RegisterAsyncPostBackControl no evento Page_Load para sua página, como mostrado no exemplo o seguir:
Protected Sub Page_Load()
ScriptManager1.RegisterAsyncPostBackControl(SurveyDataList)
End Sub
protected void Page_Load()
{
ScriptManager1.RegisterAsyncPostBackControl(SurveyDataList);
}
Para atualizar o controle UpdatePanel programaticamente, você pode chamar o método Update de um controle UpdatePanel.Isso é útil se você deve executar algum processamento no servidor antes de atualizar o controle UpdatePanel.O exemplo a seguir mostra como atualizar um controle UpdatePanel programaticamente.
Protected Sub ChoicesRadioButtonList_SelectedIndexChanged(sender As Object, e As EventArgs)
Dim answers As SortedList = Me.AnsweredQuestions
Dim r As RadioButtonList = CType(sender, RadioButtonList)
answers(r.ToolTip) = r.SelectedValue
Me.AnsweredQuestions = answers
ResultsList.DataSource = Me.AnsweredQuestions
ResultsList.DataBind()
If Me.AnsweredQuestions.Count = SurveyDataList.Items.Count Then _
SubmitButton.Visible = True
UpdatePanel1.Update()
End Sub
protected void ChoicesRadioButtonList_SelectedIndexChanged(object sender, EventArgs e)
{
SortedList answers = this.AnsweredQuestions;
RadioButtonList r = (RadioButtonList)sender;
answers[r.ToolTip] = r.SelectedValue;
this.AnsweredQuestions = answers;
ResultsList.DataSource = this.AnsweredQuestions;
ResultsList.DataBind();
if (this.AnsweredQuestions.Count == SurveyDataList.Items.Count)
SubmitButton.Visible = true;
UpdatePanel1.Update();
}
O exemplo a seguir mostra uma página que registra um controle como um disparador, usando o método RegisterAsyncPostBackControl.Em seguida, por programação atualiza um controle UpdatePanel usando o método Update.
<%@ Page Language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script >
Protected Property AnsweredQuestions As SortedList
Get
If ViewState("AnsweredQuestions") IsNot Nothing Then
Return CType(ViewState("AnsweredQuestions"), SortedList)
Else
Return New SortedList()
End If
End Get
Set
ViewState("AnsweredQuestions") = value
End Set
End Property
Protected Sub Page_Load()
ScriptManager1.RegisterAsyncPostBackControl(SurveyDataList)
End Sub
Protected Sub ChoicesRadioButtonList_SelectedIndexChanged(sender As Object, e As EventArgs)
Dim answers As SortedList = Me.AnsweredQuestions
Dim r As RadioButtonList = CType(sender, RadioButtonList)
answers(r.ToolTip) = r.SelectedValue
Me.AnsweredQuestions = answers
ResultsList.DataSource = Me.AnsweredQuestions
ResultsList.DataBind()
If Me.AnsweredQuestions.Count = SurveyDataList.Items.Count Then _
SubmitButton.Visible = True
UpdatePanel1.Update()
End Sub
Protected Sub SubmitButton_Click(sender As Object, e As EventArgs)
' Submit responses.
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" >
<title>Registering Controls as Async Postback Controls</title>
<style type="text/css">
.AnswerFloatPanelStyle {
background-color: bisque;
position: absolute;
right: 10px;
height: 130px;
width: 150px;
border-right: silver thin solid; border-top: silver thin solid;
border-left: silver thin solid; border-bottom: silver thin solid;
}
</style>
</head>
<body>
<form id="form1" >
<div>
<asp:ScriptManager ID="ScriptManager1" />
<div id="AnswerFloatPanel" class="AnswerFloatPanelStyle" >
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" >
<ContentTemplate>
Completed Questions:
<asp:DataList ID="ResultsList" >
<ItemTemplate>
<asp:Label ID="ResultQuestion" Text='<%# Eval("Key") %>' />
::
<asp:Label ID="ResultAnswer" Text='<%# Eval("Value") %>' />
</ItemTemplate>
</asp:DataList>
<p style="text-align: right">
<asp:Button ID="SubmitButton" Text="Submit" Visible="false"
OnClick="SubmitButton_Click" />
</p>
<asp:Label ID="Message" runat="Server" />
</ContentTemplate>
</asp:UpdatePanel>
</div>
<asp:XmlDataSource ID="SurveyDataSource"
XPath="/Questions/Question"
DataFile="~/App_Data/SurveyQuestions.xml"/>
<asp:DataList
ID="SurveyDataList"
DataSourceID="SurveyDataSource"
>
<ItemTemplate>
<table cellpadding="2" cellspacing="2">
<tr>
<td valign="top">
<asp:Label id="QuestionLabel" Text='<%# XPath("@Title")%>' />
</td>
</tr>
<tr><td>
<asp:RadioButtonList ID="ChoicesRadioButtonList"
DataSource='<%#XPathSelect("Choices/Choice") %>'
DataTextField="InnerText" DataValueField="InnerText"
AutoPostBack="True"
ToolTip='<%# "Question" + XPath("@ID") %>'
OnSelectedIndexChanged="ChoicesRadioButtonList_SelectedIndexChanged"/>
</td></tr>
</table>
<hr />
</ItemTemplate>
</asp:DataList>
</div>
</form>
</body>
</html>
<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script >
protected SortedList AnsweredQuestions
{
get { return (SortedList)(ViewState["AnsweredQuestions"] ?? new SortedList()); }
set { ViewState["AnsweredQuestions"] = value; }
}
protected void Page_Load()
{
ScriptManager1.RegisterAsyncPostBackControl(SurveyDataList);
}
protected void ChoicesRadioButtonList_SelectedIndexChanged(object sender, EventArgs e)
{
SortedList answers = this.AnsweredQuestions;
RadioButtonList r = (RadioButtonList)sender;
answers[r.ToolTip] = r.SelectedValue;
this.AnsweredQuestions = answers;
ResultsList.DataSource = this.AnsweredQuestions;
ResultsList.DataBind();
if (this.AnsweredQuestions.Count == SurveyDataList.Items.Count)
SubmitButton.Visible = true;
UpdatePanel1.Update();
}
protected void SubmitButton_Click(object sender, EventArgs e)
{
// Submit responses.
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" >
<title>Registering Controls as Async Postback Controls</title>
<style type="text/css">
.AnswerFloatPanelStyle {
background-color: bisque;
position: absolute;
right: 10px;
height: 130px;
width: 150px;
border-right: silver thin solid; border-top: silver thin solid;
border-left: silver thin solid; border-bottom: silver thin solid;
}
</style>
</head>
<body>
<form id="form1" >
<div>
<asp:ScriptManager ID="ScriptManager1" />
<div id="AnswerFloatPanel" class="AnswerFloatPanelStyle" >
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" >
<ContentTemplate>
Completed Questions:
<asp:DataList ID="ResultsList" >
<ItemTemplate>
<asp:Label ID="ResultQuestion" Text='<%# Eval("Key") %>' />
::
<asp:Label ID="ResultAnswer" Text='<%# Eval("Value") %>' />
</ItemTemplate>
</asp:DataList>
<p style="text-align: right">
<asp:Button ID="SubmitButton" Text="Submit" Visible="false"
OnClick="SubmitButton_Click" />
</p>
<asp:Label ID="Message" runat="Server" />
</ContentTemplate>
</asp:UpdatePanel>
</div>
<asp:XmlDataSource ID="SurveyDataSource"
XPath="/Questions/Question"
DataFile="~/App_Data/SurveyQuestions.xml"/>
<asp:DataList
ID="SurveyDataList"
DataSourceID="SurveyDataSource"
>
<ItemTemplate>
<table cellpadding="2" cellspacing="2">
<tr>
<td valign="top">
<asp:Label id="QuestionLabel" Text='<%# XPath("@Title")%>' />
</td>
</tr>
<tr><td>
<asp:RadioButtonList ID="ChoicesRadioButtonList"
DataSource='<%#XPathSelect("Choices/Choice") %>'
DataTextField="InnerText" DataValueField="InnerText"
AutoPostBack="True"
ToolTip='<%# "Question" + XPath("@ID") %>'
OnSelectedIndexChanged="ChoicesRadioButtonList_SelectedIndexChanged"/>
</td></tr>
</table>
<hr />
</ItemTemplate>
</asp:DataList>
</div>
</form>
</body>
</html>
Ativar renderização parcial da página em um controle personalizado
Você pode adicionar um UpdatePanel a um controle de usuário ou a um controle personalizado.No entanto, a página que contém o controle pode não incluir o controle ScriptManager necessário com sua propriedade EnablePartialRendering definida como true.Portanto, no seu controle personalizado você pode determinar se a renderização parcial da página é ativada chamando o método GetCurrent estático do controle ScriptManager.Se não houver nenhum controle ScriptManager na página, o método GetCurrent retorna null.Caso contrário, você pode verificar o valor da propriedade EnablePartialRendering do controle ScriptManager e incluir um controle UpdatePanel se a propriedade EnablePartialRendering retorna true.
O exemplo a seguir mostra o método CreateChildControls de um controle personalizado que herda da classe CompositeControl.Se renderização parcial da página estiver ativada para a página, o controle personalizado coloca seu conteúdo em um controle UpdatePanel.
Protected Overrides Sub CreateChildControls()
MyBase.CreateChildControls()
Dim parent As Control
Dim container As Control
' Get a reference to the ScriptManager object for the page
' if one exists.
Dim sm As ScriptManager = ScriptManager.GetCurrent(Page)
If sm Is Nothing OrElse Not sm.EnablePartialRendering Then
' If partial rendering is not enabled, set the parent
' and container as a basic control.
container = New Control()
parent = container
Else
' If partial rendering is enabled, set the parent as
' a new UpdatePanel object and the container to the
' content template of the UpdatePanel object.
Dim up As UpdatePanel = New UpdatePanel()
container = up.ContentTemplateContainer
parent = up
End If
AddDataboundControls(container)
Controls.Add(parent)
End Sub
protected override void CreateChildControls() {
base.CreateChildControls();
Control parent;
Control container;
// Get a reference to the ScriptManager object for the page
// if one exists.
ScriptManager sm = ScriptManager.GetCurrent(Page);
if (sm == null || !sm.EnablePartialRendering)
{
// If partial rendering is not enabled, set the parent
// and container as a basic control.
container = new Control();
parent = container;
}
else
{
// If partial rendering is enabled, set the parent as
// a new UpdatePanel object and the container to the
// content template of the UpdatePanel object.
UpdatePanel up = new UpdatePanel();
container = up.ContentTemplateContainer;
parent = up;
}
AddDataboundControls(container);
Controls.Add(parent);
}
O exemplo a seguir mostra um controle personalizado que inclui um controle UpdatePanel se a renderização parcial da página estiver ativada.
<%@ Page Language="VB" AutoEventWireup="true" %>
<%@ Register Namespace="UpdatePanelTutorialCustom.VB" TagPrefix="sample" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" >
<title>Browse Products</title>
<script >
Protected Sub ProductsView1_RowCommand(ByVal sender As Object, ByVal e As EventArgs)
ShoppingCartList.DataSource = ProductsView1.Cart
ShoppingCartList.DataBind()
End Sub
</script>
</head>
<body>
<form id="form1" >
<div>
<asp:ScriptManager ID="ScriptManager1" EnablePartialRendering="false" />
<h2>Browse Products</h2>
<sample:ProductsView ID="ProductsView1" PageSize="5" OnRowCommand="ProductsView1_RowCommand" />
<asp:UpdatePanel ID="CartUpdatePanel">
<ContentTemplate>
<h3>Selected Items</h3>
<asp:BulletedList BulletStyle="numbered" ID="ShoppingCartList" />
</ContentTemplate>
</asp:UpdatePanel>
</div>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="true" %>
<%@ Register Namespace="UpdatePanelTutorialCustom.CS" TagPrefix="sample" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head >
<title>Browse Products</title>
<script >
protected void ProductsView1_RowCommand(object sender, EventArgs e)
{
ShoppingCartList.DataSource = ProductsView1.Cart;
ShoppingCartList.DataBind();
}
</script>
</head>
<body>
<form id="form1" >
<div>
<asp:ScriptManager ID="ScriptManager1" EnablePartialRendering="false" />
<h2>Browse Products</h2>
<sample:ProductsView ID="ProductsView1" PageSize="5" OnRowCommand="ProductsView1_RowCommand" />
<asp:UpdatePanel ID="CartUpdatePanel">
<ContentTemplate>
<h3>Selected Items</h3>
<asp:BulletedList BulletStyle="numbered" ID="ShoppingCartList" />
</ContentTemplate>
</asp:UpdatePanel>
</div>
</form>
</body>
</html>
Imports System
Imports System.Data
Imports System.Configuration
Imports System.Collections
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls
Imports System.Web.UI
Imports System.Drawing
Namespace UpdatePanelTutorialCustom.VB
Public Class ProductsView
Inherits CompositeControl
Private _pageSize As Integer
Private _cart As ArrayList
Private Shared ReadOnly EventRowCommand As Object = New Object()
Public Property PageSize() As Integer
Get
Return _pageSize
End Get
Set(ByVal value As Integer)
_pageSize = value
End Set
End Property
Public ReadOnly Property Cart() As ArrayList
Get
Return _cart
End Get
End Property
Protected Overrides Sub CreateChildControls()
MyBase.CreateChildControls()
Dim parent As Control
Dim container As Control
' Get a reference to the ScriptManager object for the page
' if one exists.
Dim sm As ScriptManager = ScriptManager.GetCurrent(Page)
If sm Is Nothing OrElse Not sm.EnablePartialRendering Then
' If partial rendering is not enabled, set the parent
' and container as a basic control.
container = New Control()
parent = container
Else
' If partial rendering is enabled, set the parent as
' a new UpdatePanel object and the container to the
' content template of the UpdatePanel object.
Dim up As UpdatePanel = New UpdatePanel()
container = up.ContentTemplateContainer
parent = up
End If
AddDataboundControls(container)
Controls.Add(parent)
End Sub
Private Sub GridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)
Dim productID As String
If e.CommandName = "AddToCart" Then
productID = CType(sender, GridView).DataKeys(Convert.ToInt32(e.CommandArgument)).Value.ToString()
If _cart Is Nothing Then GetCart()
If _cart.IndexOf(productID) = -1 Then _
_cart.Add(productID)
ViewState("Cart") = _cart
End If
If e.CommandName = "RemoveFromCart" Then
productID = CType(sender, GridView).DataKeys(Convert.ToInt32(e.CommandArgument)).Value.ToString()
If _cart Is Nothing Then GetCart()
_cart.Remove(productID)
ViewState("Cart") = _cart
End If
Me.OnRowCommand(New EventArgs())
End Sub
Private Sub GetCart()
If ViewState("Cart") Is Nothing Then
_cart = New ArrayList()
Else
_cart = CType(ViewState("Cart"), ArrayList)
End If
End Sub
Custom Event RowCommand As EventHandler
RaiseEvent(ByVal sender As Object, ByVal e As EventArgs)
End RaiseEvent
AddHandler(ByVal value As EventHandler)
Events.AddHandler(EventRowCommand, value)
End AddHandler
RemoveHandler(ByVal value As EventHandler)
Events.RemoveHandler(EventRowCommand, value)
End RemoveHandler
End Event
Protected Overridable Sub OnRowCommand(ByVal e As EventArgs)
Dim handler As EventHandler = CType(Events(EventRowCommand), EventHandler)
If handler IsNot Nothing Then
handler(Me, e)
End If
End Sub
Private Sub AddDataboundControls(ByVal parent As Control)
Dim ds As SqlDataSource = New SqlDataSource()
ds.ID = "ProductsSqlDataSource"
ds.ConnectionString = _
ConfigurationManager.ConnectionStrings("AdventureWorksConnectionString").ConnectionString
ds.SelectCommand = _
"SELECT Production.ProductDescription.Description, Production.Product.Name, Production.ProductPhoto.ThumbnailPhotoFileName, " & _
"Production.Product.ProductID " & _
"FROM Production.Product INNER JOIN " & _
"Production.ProductProductPhoto ON Production.Product.ProductID = Production.ProductProductPhoto.ProductID INNER JOIN " & _
"Production.ProductPhoto ON Production.ProductProductPhoto.ProductPhotoID = Production.ProductPhoto.ProductPhotoID INNER JOIN " & _
"Production.ProductModelProductDescriptionCulture ON " & _
"Production.Product.ProductModelID = Production.ProductModelProductDescriptionCulture.ProductModelID INNER JOIN " & _
"Production.ProductDescription ON " & _
"Production.ProductModelProductDescriptionCulture.ProductDescriptionID = Production.ProductDescription.ProductDescriptionID"
Dim gv As GridView = New GridView()
gv.ID = "ProductsGridView"
gv.DataSourceID = ds.ID
gv.AutoGenerateColumns = False
gv.DataKeyNames = New String() {"ProductID"}
gv.GridLines = GridLines.None
gv.HeaderStyle.BackColor = Color.LightGray
gv.AlternatingRowStyle.BackColor = Color.LightBlue
gv.AllowPaging = True
gv.PageSize = _pageSize
AddHandler gv.RowCommand, AddressOf Me.GridView_RowCommand
Dim if1 As ImageField = New ImageField()
if1.HeaderText = "Product"
if1.DataImageUrlField = "ThumbnailPhotoFileName"
if1.DataImageUrlFormatString = "..\images\thumbnails\{0}"
Dim bf1 As BoundField = New BoundField()
bf1.HeaderText = "Name"
bf1.DataField = "Name"
Dim bf2 As BoundField = New BoundField()
bf2.HeaderText = "Description"
bf2.DataField = "Description"
Dim btf1 As ButtonField = New ButtonField()
btf1.Text = "Add"
btf1.CommandName = "AddToCart"
Dim btf2 As ButtonField = New ButtonField()
btf2.Text = "Remove"
btf2.CommandName = "RemoveFromCart"
gv.Columns.Add(if1)
gv.Columns.Add(bf1)
gv.Columns.Add(bf2)
gv.Columns.Add(btf1)
gv.Columns.Add(btf2)
parent.Controls.Add(New LiteralControl("<br />"))
parent.Controls.Add(gv)
parent.Controls.Add(New LiteralControl("<br />"))
parent.Controls.Add(ds)
End Sub
End Class
End Namespace
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Web.UI;
using System.Drawing;
namespace UpdatePanelTutorialCustom.CS
{
public class ProductsView : CompositeControl
{
private int _pageSize;
private ArrayList _cart;
private static readonly object EventRowCommand = new object();
public int PageSize
{
get { return _pageSize; }
set { _pageSize = value; }
}
public ArrayList Cart
{
get { return _cart; }
}
protected override void CreateChildControls() {
base.CreateChildControls();
Control parent;
Control container;
// Get a reference to the ScriptManager object for the page
// if one exists.
ScriptManager sm = ScriptManager.GetCurrent(Page);
if (sm == null || !sm.EnablePartialRendering)
{
// If partial rendering is not enabled, set the parent
// and container as a basic control.
container = new Control();
parent = container;
}
else
{
// If partial rendering is enabled, set the parent as
// a new UpdatePanel object and the container to the
// content template of the UpdatePanel object.
UpdatePanel up = new UpdatePanel();
container = up.ContentTemplateContainer;
parent = up;
}
AddDataboundControls(container);
Controls.Add(parent);
}
private void GridView_RowCommand(object sender, GridViewCommandEventArgs e)
{
string productID;
if (e.CommandName == "AddToCart")
{
productID = ((GridView)sender).DataKeys[Convert.ToInt32(e.CommandArgument)].Value.ToString();
if (_cart == null) { GetCart(); }
if (_cart.IndexOf(productID) == -1)
_cart.Add(productID);
ViewState["Cart"] = _cart;
}
if (e.CommandName == "RemoveFromCart")
{
productID = ((GridView)sender).DataKeys[Convert.ToInt32(e.CommandArgument)].Value.ToString();
if (_cart == null) { GetCart(); }
_cart.Remove(productID);
ViewState["Cart"] = _cart;
}
this.OnRowCommand(new EventArgs());
}
private void GetCart()
{
if (ViewState["Cart"] == null)
_cart = new ArrayList();
else
_cart = (ArrayList)ViewState["Cart"];
}
public event EventHandler RowCommand
{
add { Events.AddHandler(EventRowCommand, value); }
remove { Events.RemoveHandler(EventRowCommand, value); }
}
protected virtual void OnRowCommand(EventArgs e)
{
EventHandler handler = (EventHandler)Events[EventRowCommand];
if (handler != null)
{
handler(this, e);
}
}
private void AddDataboundControls(Control parent)
{
SqlDataSource ds = new SqlDataSource();
ds.ID = "ProductsSqlDataSource";
ds.ConnectionString =
ConfigurationManager.ConnectionStrings["AdventureWorksConnectionString"].ConnectionString;
ds.SelectCommand =
"SELECT Production.ProductDescription.Description, Production.Product.Name, Production.ProductPhoto.ThumbnailPhotoFileName, " +
"Production.Product.ProductID " +
"FROM Production.Product INNER JOIN " +
"Production.ProductProductPhoto ON Production.Product.ProductID = Production.ProductProductPhoto.ProductID INNER JOIN " +
"Production.ProductPhoto ON Production.ProductProductPhoto.ProductPhotoID = Production.ProductPhoto.ProductPhotoID INNER JOIN " +
"Production.ProductModelProductDescriptionCulture ON " +
"Production.Product.ProductModelID = Production.ProductModelProductDescriptionCulture.ProductModelID INNER JOIN " +
"Production.ProductDescription ON " +
"Production.ProductModelProductDescriptionCulture.ProductDescriptionID = Production.ProductDescription.ProductDescriptionID";
GridView gv = new GridView();
gv.ID = "ProductsGridView";
gv.DataSourceID = ds.ID;
gv.AutoGenerateColumns = false;
gv.DataKeyNames = new string[] { "ProductID" };
gv.GridLines = GridLines.None;
gv.HeaderStyle.BackColor = Color.LightGray;
gv.AlternatingRowStyle.BackColor = Color.LightBlue;
gv.AllowPaging = true;
gv.PageSize = _pageSize;
gv.RowCommand += this.GridView_RowCommand;
ImageField if1 = new ImageField();
if1.HeaderText = "Product";
if1.DataImageUrlField = "ThumbnailPhotoFileName";
if1.DataImageUrlFormatString = @"..\images\thumbnails\{0}";
BoundField bf1 = new BoundField();
bf1.HeaderText = "Name";
bf1.DataField = "Name";
BoundField bf2 = new BoundField();
bf2.HeaderText = "Description";
bf2.DataField = "Description";
ButtonField btf1 = new ButtonField();
btf1.Text = "Add";
btf1.CommandName = "AddToCart";
ButtonField btf2 = new ButtonField();
btf2.Text = "Remove";
btf2.CommandName = "RemoveFromCart";
gv.Columns.Add(if1);
gv.Columns.Add(bf1);
gv.Columns.Add(bf2);
gv.Columns.Add(btf1);
gv.Columns.Add(btf2);
parent.Controls.Add(new LiteralControl("<br />"));
parent.Controls.Add(gv);
parent.Controls.Add(new LiteralControl("<br />"));
parent.Controls.Add(ds);
}
}
}
Consulte também
Conceitos
Visão geral de renderização de página parcial