GridViewEditEventHandler Delegat
Definition
Wichtig
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Stellt die Methode dar, die das RowEditing-Ereignis eines GridView-Steuerelements behandelt.
public delegate void GridViewEditEventHandler(System::Object ^ sender, GridViewEditEventArgs ^ e);public delegate void GridViewEditEventHandler(object sender, GridViewEditEventArgs e);type GridViewEditEventHandler = delegate of obj * GridViewEditEventArgs -> unitPublic Delegate Sub GridViewEditEventHandler(sender As Object, e As GridViewEditEventArgs)Parameter
- sender
- Object
Die Quelle des Ereignisses.
Ein GridViewEditEventArgs-Objekt, das die Ereignisdaten enthält.
Beispiele
Im folgenden Beispiel wird veranschaulicht, wie sie dem RowEditing Ereignis eines Steuerelements programmgesteuert einen GridViewGridViewEditEventHandler Delegaten hinzufügen.
<%@ 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 Page_Load(Object sender, EventArgs e)
{
// Create a new GridView control.
GridView customersGridView = new GridView();
// Set the GridView control's properties.
customersGridView.ID = "CustomersGridView";
customersGridView.DataSourceID = "CustomersSqlDataSource";
customersGridView.AutoGenerateColumns = true;
customersGridView.AutoGenerateEditButton = true;
customersGridView.AllowPaging = true;
customersGridView.DataKeyNames = new String[] { "CustomerID" };
// Programmatically register the event-handling method.
customersGridView.RowEditing += new GridViewEditEventHandler(this.CustomersGridView_RowEditing);
// Add the GridView control to the Controls collection
// of the PlaceHolder control.
GridViewPlaceHolder.Controls.Add(customersGridView);
}
void CustomersGridView_RowEditing(Object sender, GridViewEditEventArgs e)
{
// User the sender parameter to retrieve the GridView control
// that raised the event.
GridView customersGridView = (GridView)sender;
// Get the country for the row being edited. For this example, the
// country is contained in the seventh column (index 6).
String country = customersGridView.Rows[e.NewEditIndex].Cells[6].Text;
// For this example, cancel the edit operation if the user attempts
// to edit the record of a customer from the USA.
if (country == "USA")
{
// Cancel the edit operation.
e.Cancel = true;
Message.Text = "You cannot edit this record.";
}
else
{
Message.Text = "";
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridViewEditEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewEditEventHandler Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<asp:placeholder id="GridViewPlaceHolder"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</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 Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Create a new GridView control.
Dim customersGridView As New GridView()
' Set the GridView control's properties.
customersGridView.ID = "CustomersGridView"
customersGridView.DataSourceID = "CustomersSqlDataSource"
customersGridView.AutoGenerateColumns = True
customersGridView.AutoGenerateEditButton = True
customersGridView.AllowPaging = True
Dim keyArray() As String = {"CustomerID"}
customersGridView.DataKeyNames = keyArray
' Programmatically register the event-handling method.
AddHandler customersGridView.RowEditing, AddressOf CustomersGridView_RowEditing
' Add the GridView control to the Controls collection
' of the PlaceHolder control.
GridViewPlaceHolder.Controls.Add(customersGridView)
End Sub
Sub CustomersGridView_RowEditing(ByVal sender As Object, ByVal e As GridViewEditEventArgs)
' User the sender parameter to retrieve the GridView control
' that raised the event.
Dim customersGridView As GridView = CType(sender, GridView)
' Get the country for the row being edited. For this example, the
' country is contained in the seventh column (index 6).
Dim country As String = customersGridView.Rows(e.NewEditIndex).Cells(6).Text
' For this example, cancel the edit operation if the user attempts
' to edit the record of a customer from the USA.
If country = "USA" Then
' Cancel the edit operation.
e.Cancel = True
Message.Text = "You cannot edit this record."
Else
Message.Text = ""
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridViewEditEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridViewEditEventHandler Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<asp:placeholder id="GridViewPlaceHolder"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
Im folgenden Beispiel wird veranschaulicht, wie sie dem RowEditing Ereignis eines Steuerelements deklarativ einen GridViewGridViewEditEventHandler Delegaten hinzufügen.
<%@ 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 CustomersGridView_RowEditing(Object sender, GridViewEditEventArgs e)
{
// Get the country for the row being edited. For this example, the
// country is contained in the seventh column (index 6).
String country = CustomersGridView.Rows[e.NewEditIndex].Cells[6].Text;
// For this example, cancel the edit operation if the user attempts
// to edit the record of a customer from the Unites States.
if (country == "USA")
{
// Cancel the edit operation.
e.Cancel = true;
Message.Text = "You cannot edit this record.";
}
else
{
Message.Text = "";
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView RowEditing Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowEditing Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<!-- The GridView control automatically sets the columns -->
<!-- specified in the datakeynames property as read-only. -->
<!-- No input controls are rendered for these columns in -->
<!-- edit mode. -->
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="true"
autogenerateeditbutton="true"
allowpaging="true"
datakeynames="CustomerID"
onrowediting="CustomersGridView_RowEditing"
runat="server">
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</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 CustomersGridView_RowEditing(ByVal sender As Object, ByVal e As GridViewEditEventArgs)
' Get the country for the row being edited. For this example, the
' country is contained in the seventh column (index 6).
Dim country As String = CustomersGridView.Rows(e.NewEditIndex).Cells(6).Text
' For this example, cancel the edit operation if the user attempts
' to edit the record of a customer from the United States.
If country = "USA" Then
' Cancel the edit operation.
e.Cancel = True
Message.Text = "You cannot edit this record."
Else
Message.Text = ""
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>GridView RowEditing Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>GridView RowEditing Example</h3>
<asp:label id="Message"
forecolor="Red"
runat="server"/>
<br/>
<!-- The GridView control automatically sets the columns -->
<!-- specified in the datakeynames property as read-only. -->
<!-- No input controls are rendered for these columns in -->
<!-- edit mode. -->
<asp:gridview id="CustomersGridView"
datasourceid="CustomersSqlDataSource"
autogeneratecolumns="true"
autogenerateeditbutton="true"
allowpaging="true"
datakeynames="CustomerID"
onrowediting="CustomersGridView_RowEditing"
runat="server">
</asp:gridview>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:sqldatasource id="CustomersSqlDataSource"
selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server">
</asp:sqldatasource>
</form>
</body>
</html>
Hinweise
Das RowEditing Ereignis wird ausgelöst, wenn auf eine Schaltfläche Bearbeiten (eine Schaltfläche mit CommandName der auf "Bearbeiten" festgelegten Eigenschaft) geklickt wird, aber bevor das Steuerelement in den GridView Bearbeitungsmodus wechselt. Dadurch können Sie eine Ereignisbehandlungsmethode bereitstellen, die eine benutzerdefinierte Routine ausführt, z. B. das Abbrechen des Bearbeitungsvorgangs, wenn dieses Ereignis auftritt.
Beim Erstellen eines GridViewEditEventHandler-Delegaten bestimmen Sie die Methode für die Ereignisbehandlung. Um dem Ereignishandler das Ereignis zuzuordnen, fügen Sie dem Ereignis eine Instanz des Delegaten hinzu. Der Ereignishandler wird bei jedem Eintreten des Ereignisses aufgerufen, sofern der Delegat nicht entfernt wird. Weitere Informationen zu Ereignishandlerdelegierten finden Sie unter Behandeln und Auslösen von Ereignissen.
Erweiterungsmethoden
| GetMethodInfo(Delegate) |
Ruft ein Objekt ab, das die Methode darstellt, die vom angegebenen Delegaten dargestellt wird. |
Gilt für:
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