DataGridItemEventHandler Delegate
Represents the method that will handle the ItemCreated and ItemDataBound events of a DataGrid.
[Visual Basic] <Serializable> Public Delegate Sub DataGridItemEventHandler( _ ByVal sender As Object, _ ByVal e As DataGridItemEventArgs _ ) [C#] [Serializable] public delegate void DataGridItemEventHandler( object sender, DataGridItemEventArgs e ); [C++] [Serializable] public __gc __delegate void DataGridItemEventHandler( Object* sender, DataGridItemEventArgs* e );
[JScript] In JScript, you can use the delegates in the .NET Framework, but you cannot define your own.
Parameters [Visual Basic, C#, C++]
The declaration of your event handler must have the same parameters as the DataGridItemEventHandler delegate declaration.
- sender
- The source of the event.
- e
- A DataGridItemEventArgs than contains the event data.
Remarks
The ItemCreated event is raised when an item in the DataGrid control is created.
The ItemDataBound event is raised when an item in the DataGrid control is data bound to a source.
When you create a DataGridItemEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see Events and Delegates.
Example
[Visual Basic, C#] The following example demonstrates how to specify and code a handler for the ItemCreated event to display the order in which items are created in the DataGrid control.
[Visual Basic] <%@ Page Language="VB" AutoEventWireup="True" %> <%@ Import Namespace="System.Data" %> <html> <script language="VB" runat="server"> Dim Cart As DataTable Dim CartView As DataView Function CreateDataSource() As ICollection Dim dt As New DataTable() Dim dr As DataRow dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32))) dt.Columns.Add(New DataColumn("StringValue", GetType(String))) dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double))) Dim i As Integer For i = 0 To 9 dr = dt.NewRow() dr(0) = i dr(1) = "Item " & i.ToString() dr(2) = 1.23 *(i + 1) dt.Rows.Add(dr) Next i Dim dv As New DataView(dt) Return dv End Function 'CreateDataSource Sub Page_Load(sender As Object, e As EventArgs) If Not IsPostBack Then ' Need to load this data only once. ItemsGrid.DataSource = CreateDataSource() ItemsGrid.DataBind() End If End Sub 'Page_Load Sub Item_Created(sender As Object, e As DataGridItemEventArgs) Label1.Text = Label1.Text & " " & e.Item.ItemIndex End Sub 'Item_Created </script> <body> <form runat=server> <h3>DataGridItemEventArgs Example</h3> <asp:DataGrid id="ItemsGrid" runat="server" BorderColor="black" BorderWidth="1" CellPadding="3" ShowFooter="true" OnItemCreated="Item_Created" AutoGenerateColumns="true"> <HeaderStyle BackColor="#00aaaa"> </HeaderStyle> <FooterStyle BackColor="#00aaaa"> </FooterStyle> </asp:DataGrid> <br> <asp:Label id="Label1" Text="Order of items created: " runat="server"/> <br> <asp:Label id="Label2" Text="Note: The -1's refer to the header and footer." runat="server"/> </form> </body> </html> [C#] <%@ Page Language="C#" AutoEventWireup="True" %> <%@ Import Namespace="System.Data" %> <html> <script language="C#" runat="server"> DataTable Cart; DataView CartView; ICollection CreateDataSource() { DataTable dt = new DataTable(); DataRow dr; dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32))); dt.Columns.Add(new DataColumn("StringValue", typeof(string))); dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double))); for (int i = 0; i < 10; i++) { dr = dt.NewRow(); dr[0] = i; dr[1] = "Item " + i.ToString(); dr[2] = 1.23 * (i+1); dt.Rows.Add(dr); } DataView dv = new DataView(dt); return dv; } void Page_Load(Object sender, EventArgs e) { if (!IsPostBack) { // Need to load this data only once. ItemsGrid.DataSource = CreateDataSource(); ItemsGrid.DataBind(); } } void Item_Created(Object sender, DataGridItemEventArgs e) { Label1.Text = Label1.Text + " " + e.Item.ItemIndex; } </script> <body> <form runat=server> <h3>DataGridItemEventArgs Example</h3> <asp:DataGrid id="ItemsGrid" runat="server" BorderColor="black" BorderWidth="1" CellPadding="3" ShowFooter="true" OnItemCreated="Item_Created" AutoGenerateColumns="true"> <HeaderStyle BackColor="#00aaaa"> </HeaderStyle> <FooterStyle BackColor="#00aaaa"> </FooterStyle> </asp:DataGrid> <br> <asp:Label id="Label1" Text="Order of items created: " runat="server"/> <br> <asp:Label id="Label2" Text="Note: The -1's refer to the header and footer." runat="server"/> </form> </body> </html> [Visual Basic] <%@ Page Language="VB" AutoEventWireup="True" %> <%@ Import Namespace="System.Data" %> <html> <script runat="server"> Function CreateDataSource() As ICollection ' Create sample data for the DataGrid control. Dim dt As DataTable = New DataTable() Dim dr As DataRow ' Define the columns of the table. dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32))) dt.Columns.Add(New DataColumn("StringValue", GetType(String))) dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double))) ' Populate the table with sample values. Dim i As Integer For i=0 To 10 dr = dt.NewRow() dr(0) = i dr(1) = "Item " & i.ToString() dr(2) = 1.23 * (i + 1) dt.Rows.Add(dr) Next i Dim dv As DataView = New DataView(dt) return dv End Function Sub Page_Load(sender As Object, e As EventArgs) ' Load sample data only once, when the page is first loaded. If Not IsPostBack Then ItemsGrid.DataSource = CreateDataSource() ItemsGrid.DataBind() End If End Sub Sub Item_Bound(sender As Object, e As DataGridItemEventArgs) ' Use the ItemDataBound event to customize the DataGrid control. ' The ItemDataBound event allows you to access the data before ' the item is displayed in the control. In this example, the ' ItemDataBound event is used to format the items in the ' CurrencyColumn in currency format. If e.Item.ItemType = ListItemType.Item Or _ e.Item.ItemType = ListItemType.AlternatingItem Then ' Retrieve the text of the CurrencyColumn from the DataGridItem ' and convert the value to a Double. Dim Price As Double = Convert.ToDouble(e.Item.Cells(2).Text) ' Format the value as currency and redisplay it in the DataGrid. e.Item.Cells(2).Text = Price.ToString("c") End If End Sub </script> <body> <form runat=server> <h3>DataGrid ItemDataBound Example</h3> <asp:DataGrid id="ItemsGrid" runat="server" BorderColor="black" BorderWidth="1" CellPadding="3" ShowFooter="true" OnItemDataBound="Item_Bound"> <HeaderStyle BackColor="#00aaaa"> </HeaderStyle> <FooterStyle BackColor="#00aaaa"> </FooterStyle> </asp:DataGrid> </form> </body> </html> [C#] <%@ Page Language="C#" AutoEventWireup="True" Debug="true" %> <%@ Import Namespace="System.Data" %> <html> <script runat="server"> ICollection CreateDataSource() { // Create sample data for the DataGrid control. DataTable dt = new DataTable(); DataRow dr; // Define the columns of the table. dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32))); dt.Columns.Add(new DataColumn("StringValue", typeof(String))); dt.Columns.Add(new DataColumn("CurrencyValue", typeof(Double))); // Populate the table with sample values. for (int i=0; i<=10; i++) { dr = dt.NewRow(); dr[0] = i; dr[1] = "Item " + i.ToString(); dr[2] = 1.23 * (i + 1); dt.Rows.Add(dr); } DataView dv = new DataView(dt); return dv; } void Page_Load(Object sender, EventArgs e) { // Load sample data only once, when the page is first loaded. if (!IsPostBack) { ItemsGrid.DataSource = CreateDataSource(); ItemsGrid.DataBind(); } } void Item_Bound(Object sender, DataGridItemEventArgs e) { // Use the ItemDataBound event to customize the DataGrid control. // The ItemDataBound event allows you to access the data before // the item is displayed in the control. In this example, the // ItemDataBound event is used to format the items in the // CurrencyColumn in currency format. if((e.Item.ItemType == ListItemType.Item) || (e.Item.ItemType == ListItemType.AlternatingItem)) { // Retrieve the text of the CurrencyColumn from the DataGridItem // and convert the value to a Double. Double Price = Convert.ToDouble(e.Item.Cells[2].Text); // Format the value as currency and redisplay it in the DataGrid. e.Item.Cells[2].Text = Price.ToString("c"); } } </script> <body> <form runat=server> <h3>DataGrid ItemDataBound Example</h3> <asp:DataGrid id="ItemsGrid" runat="server" BorderColor="black" BorderWidth="1" CellPadding="3" ShowFooter="true" OnItemDataBound="Item_Bound"> <HeaderStyle BackColor="#00aaaa"> </HeaderStyle> <FooterStyle BackColor="#00aaaa"> </FooterStyle> </asp:DataGrid> </form> </body> </html> [Visual Basic] <%@ Page Language="VB" AutoEventWireup="True" %> <%@ Import Namespace="System.Data" %> <html> <script runat="server"> Function CreateDataSource() As ICollection ' Create sample data for the DataGrid control. Dim dt As DataTable = New DataTable() Dim dr As DataRow ' Define the columns of the table. dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32))) dt.Columns.Add(New DataColumn("StringValue", GetType(String))) dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double))) ' Populate the table with sample values. Dim i As Integer For i=0 To 10 dr = dt.NewRow() dr(0) = i dr(1) = "Item " & i.ToString() dr(2) = 1.23 * (i + 1) dt.Rows.Add(dr) Next i Dim dv As DataView = New DataView(dt) return dv End Function Sub Page_Load(sender As Object, e As EventArgs) ' Manually register the event-handling method for the ' ItemDataBound event of the DataGrid control. AddHandler ItemsGrid.ItemDataBound, AddressOf Item_Bound ' Load sample data only once, when the page is first loaded. If Not IsPostBack Then ItemsGrid.DataSource = CreateDataSource() ItemsGrid.DataBind() End If End Sub Sub Item_Bound(sender As Object, e As DataGridItemEventArgs) ' Use the ItemDataBound event to customize the DataGrid control. ' The ItemDataBound event allows you to access the data before ' the item is displayed in the control. In this example, the ' ItemDataBound event is used to format the items in the ' CurrencyColumn in currency format. If e.Item.ItemType = ListItemType.Item Or _ e.Item.ItemType = ListItemType.AlternatingItem Then ' Retrieve the text of the CurrencyColumn from the DataGridItem ' and convert the value to a Double. Dim Price As Double = Convert.ToDouble(e.Item.Cells(2).Text) ' Format the value as currency and redisplay it in the DataGrid. e.Item.Cells(2).Text = Price.ToString("c") End If End Sub </script> <body> <form runat=server> <h3>DataGrid ItemDataBound Example</h3> <asp:DataGrid id="ItemsGrid" runat="server" BorderColor="black" BorderWidth="1" CellPadding="3" ShowFooter="true"> <HeaderStyle BackColor="#00aaaa"> </HeaderStyle> <FooterStyle BackColor="#00aaaa"> </FooterStyle> </asp:DataGrid> </form> </body> </html> [C#] <%@ Page Language="C#" AutoEventWireup="True" %> <%@ Import Namespace="System.Data" %> <html> <script runat="server"> ICollection CreateDataSource() { // Create sample data for the DataGrid control. DataTable dt = new DataTable(); DataRow dr; // Define the columns of the table. dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32))); dt.Columns.Add(new DataColumn("StringValue", typeof(String))); dt.Columns.Add(new DataColumn("CurrencyValue", typeof(Double))); // Populate the table with sample values. for (int i=0; i<=10; i++) { dr = dt.NewRow(); dr[0] = i; dr[1] = "Item " + i.ToString(); dr[2] = 1.23 * (i + 1); dt.Rows.Add(dr); } DataView dv = new DataView(dt); return dv; } void Page_Load(Object sender, EventArgs e) { // Manually register the event-handling method for the // ItemDataBound event of the DataGrid control. ItemsGrid.ItemDataBound += new DataGridItemEventHandler(this.Item_Bound); // Load sample data only once, when the page is first loaded. if (!IsPostBack) { ItemsGrid.DataSource = CreateDataSource(); ItemsGrid.DataBind(); } } void Item_Bound(Object sender, DataGridItemEventArgs e) { // Use the ItemDataBound event to customize the DataGrid control. // The ItemDataBound event allows you to access the data before // the item is displayed in the control. In this example, the // ItemDataBound event is used to format the items in the // CurrencyColumn in currency format. if((e.Item.ItemType == ListItemType.Item) || (e.Item.ItemType == ListItemType.AlternatingItem)) { // Retrieve the text of the CurrencyColumn from the DataGridItem // and convert the value to a Double. Double Price = Convert.ToDouble(e.Item.Cells[2].Text); // Format the value as currency and redisplay it in the DataGrid. e.Item.Cells[2].Text = Price.ToString("c"); } } </script> <body> <form runat=server> <h3>DataGrid ItemDataBound Example</h3> <asp:DataGrid id="ItemsGrid" runat="server" BorderColor="black" BorderWidth="1" CellPadding="3" ShowFooter="true"> <HeaderStyle BackColor="#00aaaa"> </HeaderStyle> <FooterStyle BackColor="#00aaaa"> </FooterStyle> </asp:DataGrid> </form> </body> </html>
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Requirements
Namespace: System.Web.UI.WebControls
Platforms: Windows 2000, Windows XP Professional, Windows Server 2003 family
Assembly: System.Web (in System.Web.dll)
See Also
System.Web.UI.WebControls Namespace | DataGridItemEventArgs | DataGrid | ItemCreated | ItemDataBound