GridView.OnRowCreated(GridViewRowEventArgs) Metodo
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Genera l'evento RowCreated.
protected:
virtual void OnRowCreated(System::Web::UI::WebControls::GridViewRowEventArgs ^ e);protected virtual void OnRowCreated (System.Web.UI.WebControls.GridViewRowEventArgs e);abstract member OnRowCreated : System.Web.UI.WebControls.GridViewRowEventArgs -> unit
override this.OnRowCreated : System.Web.UI.WebControls.GridViewRowEventArgs -> unitProtected Overridable Sub OnRowCreated (e As GridViewRowEventArgs)Parametri
GridViewRowEventArgs in cui sono contenuti i dati dell'evento.
Esempio
Nell'esempio seguente viene illustrato come fornire un metodo di gestione degli eventi per l'evento RowCreated . Quando viene creata una riga, il relativo indice viene archiviato nella CommandArgument proprietà di un LinkButton controllo contenuto nella nuova riga. In questo modo è possibile determinare l'indice della riga quando l'utente fa clic sul pulsante di comando.
<%@ Page language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void ProductsGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
{
// If multiple buttons are used in a GridView control, use the
// CommandName property to determine which button was clicked.
if(e.CommandName=="Add")
{
// Convert the row index stored in the CommandArgument
// property to an Integer.
int index = Convert.ToInt32(e.CommandArgument);
// Retrieve the row that contains the button clicked
// by the user from the Rows collection.
GridViewRow row = ProductsGridView.Rows[index];
// Create a new ListItem object for the product in the row.
ListItem item = new ListItem();
item.Text = Server.HtmlDecode(row.Cells[1].Text);
// If the product is not already in the ListBox, add the ListItem
// object to the Items collection of the ListBox control.
if (!ProductsListBox.Items.Contains(item))
{
ProductsListBox.Items.Add(item);
}
}
}
void ProductsGridView_RowCreated(Object sender, GridViewRowEventArgs e)
{
// The GridViewCommandEventArgs class does not contain a
// property that indicates which row's command button was
// clicked. To identify which row's button was clicked, use
// the button's CommandArgument property by setting it to the
// row's index.
if(e.Row.RowType == DataControlRowType.DataRow)
{
// Retrieve the LinkButton control from the first column.
LinkButton addButton = (LinkButton)e.Row.FindControl("AddButton");
// Set the LinkButton's CommandArgument property with the
// row's index.
addButton.CommandArgument = e.Row.RowIndex.ToString();
}
}
</script>
<html>
<head id="Head1" runat="server">
<title>GridView RowCreated Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowCreated Example</h3>
<table width="100%">
<tr>
<td style="width:50%">
<asp:GridView ID="ProductsGridView"
DataSourceID="ProductsDataSource"
AllowPaging="true"
AutoGenerateColumns="false"
OnRowCommand="ProductsGridView_RowCommand"
OnRowCreated="ProductsGridView_RowCreated"
runat="server">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:LinkButton runat="server"
ID="AddButton"
CommandName="Add"
Text="Add" />
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="Name"
HeaderText="Product Name"/>
<asp:BoundField DataField="ProductNumber"
HeaderText="Product Number"/>
</Columns>
</asp:GridView>
</td>
<td style="vertical-align:top; width:50%">
Products: <br/>
<asp:listbox id="ProductsListBox"
runat="server" Height="200px" Width="200px"/>
</td>
</tr>
</table>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the AdventureWorks sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="ProductsDataSource"
selectcommand="Select [Name], [ProductNumber] From Production.Product"
connectionstring="<%$ ConnectionStrings:AdventureWorks_DataConnectionString%>"
runat="server"/>
</form>
</body>
</html>
<%@ Page language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub ProductsGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)
' If multiple buttons are used in a GridView control, use the
' CommandName property to determine which button was clicked.
If e.CommandName = "Add" Then
' Convert the row index stored in the CommandArgument
' property to an Integer.
Dim index As Integer = Convert.ToInt32(e.CommandArgument)
' Retrieve the row that contains the button clicked
' by the user from the Rows collection.
Dim row As GridViewRow = ProductsGridView.Rows(index)
' Create a new ListItem object for the product in the row.
Dim item As New ListItem()
item.Text = Server.HtmlDecode(row.Cells(1).Text)
' If the product is not already in the ListBox, add the ListItem
' object to the Items collection of the ListBox control.
If Not ProductsListBox.Items.Contains(item) Then
ProductsListBox.Items.Add(item)
End If
End If
End Sub
Sub ProductsGridView_RowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
' The GridViewCommandEventArgs class does not contain a
' property that indicates which row's command button was
' clicked. To identify which row's button was clicked, use
' the button's CommandArgument property by setting it to the
' row's index.
If e.Row.RowType = DataControlRowType.DataRow Then
' Retrieve the LinkButton control from the first column.
Dim addButton As LinkButton = CType(e.Row.FindControl("AddButton"), LinkButton)
' Set the LinkButton's CommandArgument property with the
' row's index.
addButton.CommandArgument = e.Row.RowIndex.ToString()
End If
End Sub
</script>
<html>
<head id="Head1" runat="server">
<title>GridView RowCreated Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowCreated Example</h3>
<table width="100%">
<tr>
<td style="width:50%">
<asp:GridView ID="ProductsGridView"
DataSourceID="ProductsDataSource"
AllowPaging="true"
AutoGenerateColumns="false"
OnRowCommand="ProductsGridView_RowCommand"
OnRowCreated="ProductsGridView_RowCreated"
runat="server">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:LinkButton runat="server"
ID="AddButton"
CommandName="Add"
Text="Add" />
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="Name"
HeaderText="Product Name"/>
<asp:BoundField DataField="ProductNumber"
HeaderText="Product Number"/>
</Columns>
</asp:GridView>
</td>
<td style="vertical-align:top; width:50%">
Products: <br/>
<asp:listbox id="ProductsListBox"
runat="server" Height="200px" Width="200px"/>
</td>
</tr>
</table>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the AdventureWorks sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="ProductsDataSource"
selectcommand="Select [Name], [ProductNumber] From Production.Product"
connectionstring="<%$ ConnectionStrings:AdventureWorks_DataConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Commenti
Prima di poter eseguire il rendering del GridView controllo, è necessario creare un GridViewRow oggetto per ogni riga nel controllo . L'evento RowCreated viene generato quando viene creata ogni riga nel GridView controllo . In questo modo è possibile fornire un metodo di gestione degli eventi che esegue una routine personalizzata, ad esempio l'aggiunta di contenuto personalizzato a una riga, ogni volta che si verifica questo evento.
Quando viene generato un evento, il gestore dell'evento viene richiamato tramite un delegato. Per altre informazioni, vedere la gestione e generazione di eventi.
Il metodo OnRowCreated consente inoltre alle classi derivate di gestire l'evento senza associare un delegato. È la tecnica consigliata per la gestione dell'evento in una classe derivata.
Note per gli eredi
Quando si esegue l'override di OnRowCreated(GridViewRowEventArgs) in una classe derivata, verificare di chiamare il metodo OnRowCreated(GridViewRowEventArgs) della classe di base in modo che i delegati registrati ricevano l'evento.
