<%@ Page Language="VB" %>
<%@ Import Namespace="System.Web.Script.Serialization" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Dim serializer As JavaScriptSerializer
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
serializer = New JavaScriptSerializer()
' Register the custom converter.
serializer.RegisterConverters(New JavaScriptConverter() _
{New System.Web.Script.Serialization.VB.ListItemCollectionConverter()})
End Sub
Protected Sub saveButton_Click(ByVal sender As Object, ByVal e As EventArgs)
' Save the current state of the ListBox control.
SavedState.Text = serializer.Serialize(ListBox1.Items)
recoverButton.Enabled = True
Message.Text = "State saved"
End Sub
Protected Sub recoverButton_Click(ByVal sender As Object, ByVal e As EventArgs)
' Recover the saved items of the ListBox control.
Dim recoveredList As ListItemCollection = _
serializer.Deserialize(Of ListItemCollection)(SavedState.Text)
Dim newListItemArray(recoveredList.Count - 1) As ListItem
recoveredList.CopyTo(newListItemArray, 0)
ListBox1.Items.Clear()
ListBox1.Items.AddRange(newListItemArray)
Message.Text = "Last saved state recovered."
End Sub
Protected Sub clearButton_Click(ByVal sender As Object, ByVal e As EventArgs)
' Remove all items from the ListBox control.
ListBox1.Items.Clear()
Message.Text = "All items removed"
End Sub
Protected Sub ContactsGrid_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
' Get the currently selected row using the SelectedRow property.
Dim row As GridViewRow = ContactsGrid.SelectedRow
' Get the ID of the item selected.
Dim itemId As String = ContactsGrid.DataKeys(row.RowIndex).Value.ToString()
Dim newItem As ListItem = New ListItem(row.Cells(4).Text, itemId)
' Check if the item already exists in the ListBox control.
If Not ListBox1.Items.Contains(newItem) Then
' Add the item to the ListBox control.
ListBox1.Items.Add(newItem)
Message.Text = "Item added"
Else
Message.Text = "Item already exists"
End If
End Sub
Private Function SearchItem(ByVal itemId As String) As Boolean
Dim i As Integer
For i = 0 To ListBox1.Items.Count - 1
If ListBox1.Items(i).Value = itemId Then
Return True
End If
Next i
Return False
End Function
Protected Sub ContactsGrid_PageIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
ContactsGrid.SelectedIndex = -1
End Sub
Protected Sub searchButton_Click(ByVal sender As Object, ByVal e As EventArgs)
ContactsGrid.SelectedIndex = -1
ContactsGrid.PageIndex = 0
ScriptManager1.SetFocus(TextBox1)
End Sub
Protected Sub CheckBox1_CheckedChanged(ByVal sender As Object, ByVal e As EventArgs)
SavedState.Visible = CheckBox1.Checked
StateLabel.Visible = CheckBox1.Checked
End Sub
</script>
<html >
<head runat="server">
<title>Save/Recover state</title>
<style type="text/css">
body { font: 11pt Trebuchet MS;
font-color: #000000;
padding-top: 72px;
text-align: center }
.text { font: 8pt Trebuchet MS }
</style>
</head>
<body>
<form id="form1" runat="server" defaultbutton="searchButton" defaultfocus="TextBox1">
<h3>
<span style="text-decoration: underline">
Contacts Selection</span><br />
</h3>
<asp:ScriptManager runat="server" ID="ScriptManager1" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
Type contact's first name:
<asp:TextBox ID="TextBox1" runat="server" />
<asp:Button ID="searchButton" runat="server" Text="Search" OnClick="searchButton_Click" />
<br />
<br />
<table border="0" width="100%">
<tr>
<td style="width:50%" valign="top" align="center">
<b>Search results:</b><br />
<asp:GridView ID="ContactsGrid" runat="server" AutoGenerateColumns="False"
CellPadding="4" DataKeyNames="ContactID" DataSourceID="SqlDataSource1"
OnSelectedIndexChanged="ContactsGrid_SelectedIndexChanged" ForeColor="#333333" GridLines="None" AllowPaging="True" PageSize="7" OnPageIndexChanged="ContactsGrid_PageIndexChanged">
<Columns>
<asp:CommandField ShowSelectButton="True" ButtonType="Button" />
<asp:BoundField DataField="ContactID" HeaderText="ContactID" SortExpression="ContactID" Visible="False" />
<asp:BoundField DataField="FirstName" HeaderText="FirstName" SortExpression="FirstName" />
<asp:BoundField DataField="LastName" HeaderText="LastName" SortExpression="LastName" />
<asp:BoundField DataField="EmailAddress" HeaderText="EmailAddress" SortExpression="EmailAddress" />
</Columns>
<RowStyle BackColor="#F7F6F3" ForeColor="#333333" />
<HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
<AlternatingRowStyle BackColor="White" ForeColor="#284775" />
<FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
<EditRowStyle BackColor="#999999" />
<SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
<PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
<EmptyDataTemplate>No data found.</EmptyDataTemplate>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:AdventureWorksConnectionString %>"
SelectCommand="SELECT ContactID, FirstName, LastName, EmailAddress FROM Person.Contact WHERE (UPPER(FirstName) = UPPER(@FIRSTNAME))" >
<SelectParameters>
<asp:ControlParameter Name="FIRSTNAME" ControlId="TextBox1" Type="String" />
</SelectParameters>
</asp:SqlDataSource>
</td>
<td valign="top">
<b>Contacts list:</b><br />
<asp:ListBox ID="ListBox1" runat="server" Height="200px" Width="214px" /><br />
<asp:Button ID="saveButton" runat="server" Text="Save state" OnClick="saveButton_Click" ToolTip="Save the current state of the list" />
<asp:Button ID="recoverButton" runat="server" Text="Recover saved state" OnClick="recoverButton_Click" Enabled="false" ToolTip="Recover the last saved state" />
<asp:Button ID="clearButton" runat="server" Text="Clear" OnClick="clearButton_Click" ToolTip="Remove all items from the list" /><br />
<br />
<asp:CheckBox ID="CheckBox1" runat="server" Checked="True" OnCheckedChanged="CheckBox1_CheckedChanged"
Text="Show saved state" AutoPostBack="True" /></td>
</tr>
<tr>
<td colspan="2">
<br />
<br />
<hr />
Message: <asp:Label ID="Message" runat="server" ForeColor="SteelBlue" /> <br />
<asp:Label ID="StateLabel" runat="server" Text="State:"></asp:Label>
<asp:Label ID="SavedState" runat="server"/><br />
</td>
</tr>
</table>
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdateProgress ID="UpdateProgress1" runat="server">
<ProgressTemplate>
<asp:Image ID="Image1" runat="server" ImageUrl="..\images\spinner.gif" /> Processing...
</ProgressTemplate>
</asp:UpdateProgress>
</form>
</body>
</html>
