DetailsViewInsertEventHandler Delegat
Definition
Wichtig
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Stellt die Methode dar, die das ItemInserting-Ereignis eines DetailsView-Steuerelements behandelt.
public delegate void DetailsViewInsertEventHandler(System::Object ^ sender, DetailsViewInsertEventArgs ^ e);
public delegate void DetailsViewInsertEventHandler(object sender, DetailsViewInsertEventArgs e);
type DetailsViewInsertEventHandler = delegate of obj * DetailsViewInsertEventArgs -> unit
Public Delegate Sub DetailsViewInsertEventHandler(sender As Object, e As DetailsViewInsertEventArgs)
Parameter
- sender
- Object
Die Quelle des Ereignisses.
Ein DetailsViewInsertEventArgs, das die Ereignisdaten enthält.
Beispiele
Im folgenden Codebeispiel wird veranschaulicht, wie sie dem ItemInserting Ereignis eines Steuerelements programmgesteuert einen DetailsViewDetailsViewInsertEventHandler 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 DetailsView object.
DetailsView customerDetailsView = new DetailsView();
// Set the DetailsView object's properties.
customerDetailsView.ID = "CustomerDetailsView";
customerDetailsView.DataSourceID = "DetailsViewSource";
customerDetailsView.AutoGenerateRows = true;
customerDetailsView.AutoGenerateInsertButton = true;
customerDetailsView.AllowPaging = true;
customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };
// Programmatically register the event-handling method
// for the ItemInserted event of a DetailsView control.
customerDetailsView.ItemInserting += new DetailsViewInsertEventHandler(this.CustomerDetailsView_ItemInserting);
// Add the DetailsView object to the Controls collection
// of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView);
}
void CustomerDetailsView_ItemInserting(Object sender, DetailsViewInsertEventArgs e)
{
// Use the Values property to retrieve the key field value.
String keyValue = e.Values["CustomerID"].ToString();
// Insert the record only if the key field is four characters
// long; otherwise, cancel the insert operation.
if (keyValue.Length == 4)
{
// Change the key field value to upper case before inserting
// the record in the data source.
e.Values["CustomerID"] = keyValue.ToUpper();
MessageLabel.Text = "";
}
else
{
MessageLabel.Text = "The key field must have four digits.";
e.Cancel = true;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewInsertEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:PlaceHolder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
insertcommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
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 Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Create a new DetailsView object.
Dim customerDetailsView As New DetailsView()
' Set the DetailsView object's properties.
customerDetailsView.ID = "CustomerDetailsView"
customerDetailsView.DataSourceID = "DetailsViewSource"
customerDetailsView.AutoGenerateRows = True
customerDetailsView.AutoGenerateInsertButton = True
customerDetailsView.AllowPaging = True
Dim keyArray() As String = {"CustomerID"}
customerDetailsView.DataKeyNames = keyArray
' Programmatically register the event-handling method
' for the ItemInserted event of a DetailsView control.
AddHandler customerDetailsView.ItemInserting, AddressOf CustomerDetailsView_ItemInserting
' Add the DetailsView object to the Controls collection
' of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView)
End Sub
Sub CustomerDetailsView_ItemInserting(ByVal sender As Object, ByVal e As DetailsViewInsertEventArgs)
' Use the Values property to retrieve the key field value.
Dim keyValue As String = e.Values("CustomerID").ToString()
' Insert the record only if the key field is four characters
' long; otherwise, cancel the insert operation.
If keyValue.Length = 4 Then
' Change the key field value to upper case before inserting
' the record in the data source.
e.Values("CustomerID") = keyValue.ToUpper()
MessageLabel.Text = ""
Else
MessageLabel.Text = "The key field must have four digits."
e.Cancel = True
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewInsertEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:PlaceHolder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
insertcommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Im folgenden Codebeispiel wird veranschaulicht, wie sie dem ItemInserting Ereignis eines Steuerelements deklarativ einen DetailsViewDetailsViewInsertEventHandler 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 CustomerDetailsView_ItemInserting(Object sender,
DetailsViewInsertEventArgs e)
{
// Use the Values property to retrieve the key field value.
String keyValue = e.Values["CustomerID"].ToString();
// Insert the record only if the key field is four characters
// long; otherwise, cancel the insert operation.
if (keyValue.Length == 4)
{
// Change the key field value to upper case before inserting
// the record in the data source.
e.Values["CustomerID"] = keyValue.ToUpper();
MessageLabel.Text = "";
}
else
{
MessageLabel.Text = "The key field must have four digits.";
e.Cancel = true;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewInsertEventHandler Example</h3>
<asp:detailsview id="CustomerDetailsView"
datasourceid="DetailsViewSource"
datakeynames="CustomerID"
autogenerateinsertbutton="true"
autogeneraterows="true"
allowpaging="true"
oniteminserting="CustomerDetailsView_ItemInserting"
runat="server">
<fieldheaderstyle backcolor="Navy"
forecolor="White"/>
</asp:detailsview>
<asp:label id="MessageLabel"
forecolor="Red"
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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
insertcommand="INSERT INTO [Customers]([CustomerID],
[CompanyName], [Address], [City], [PostalCode],
[Country]) VALUES (@CustomerID, @CompanyName, @Address,
@City, @PostalCode, @Country)"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
<%@ Page language="VB" autoeventwireup="false" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Sub CustomerDetailsView_ItemInserting(ByVal sender As Object, _
ByVal e As DetailsViewInsertEventArgs) _
Handles CustomerDetailsView.ItemInserting
' Use the Values property to retrieve the key field value.
Dim keyValue As String = e.Values("CustomerID").ToString()
' Insert the record only if the key field is four characters
' long; otherwise, cancel the insert operation.
If keyValue.Length = 4 Then
' Change the key field value to upper case before inserting
' the record in the data source.
e.Values("CustomerID") = keyValue.ToUpper()
MessageLabel.Text = ""
Else
MessageLabel.Text = "The key field must have four digits."
e.Cancel = True
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewInsertEventHandler Example</h3>
<asp:detailsview id="CustomerDetailsView"
datasourceid="DetailsViewSource"
datakeynames="CustomerID"
autogenerateinsertbutton="true"
autogeneraterows="true"
allowpaging="true"
oniteminserting="CustomerDetailsView_ItemInserting"
runat="server">
<fieldheaderstyle backcolor="Navy"
forecolor="White"/>
</asp:detailsview>
<asp:label id="MessageLabel"
forecolor="Red"
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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
insertcommand="INSERT INTO [Customers]([CustomerID],
[CompanyName], [Address], [City], [PostalCode],
[Country]) VALUES (@CustomerID, @CompanyName, @Address,
@City, @PostalCode, @Country)"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Hinweise
Das DetailsView -Steuerelement löst das ItemInserting -Ereignis aus, wenn auf eine Einfügen-Schaltfläche (eine Schaltfläche mit der CommandName
auf "Einfügen" festgelegten Eigenschaft) innerhalb des Steuerelements geklickt wird, aber bevor das DetailsView Steuerelement den Datensatz einfügt. Auf diese Weise können Sie einen Ereignishandler bereitstellen, der eine benutzerdefinierte Routine ausführt, z. B. die HTML-Codierung der Werte eines Datensatzes, bevor Sie ihn in die Datenquelle einfügen, wenn dieses Ereignis auftritt.
Beim Erstellen eines DetailsViewInsertEventHandler-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 Ereignishandlerdelegaten 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. |