DetailsView.ItemUpdating Ereignis
Definition
Wichtig
Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.
Tritt ein, wenn in einem DetailsView-Steuerelement auf eine Schaltfläche Aktualisieren geklickt wird, allerdings bevor der Aktualisierungsvorgang ausgeführt wird.
public:
event System::Web::UI::WebControls::DetailsViewUpdateEventHandler ^ ItemUpdating;
public event System.Web.UI.WebControls.DetailsViewUpdateEventHandler ItemUpdating;
member this.ItemUpdating : System.Web.UI.WebControls.DetailsViewUpdateEventHandler
Public Custom Event ItemUpdating As DetailsViewUpdateEventHandler
Ereignistyp
Beispiele
Im folgenden Codebeispiel wird veranschaulicht, wie das ItemUpdating -Ereignis verwendet wird, um die vom Benutzer eingegebenen Werte html zu codieren, bevor ein Datensatz in der Datenquelle aktualisiert wird.
<%@ 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 CustomerDetail_ItemInserted(object sender,
DetailsViewInsertedEventArgs e)
{
// Refresh the GridView control after a new record is inserted
// in the DetailsView control.
CustomersView.DataBind();
}
void CustomerDetail_ItemInserting(object sender,
DetailsViewInsertEventArgs e)
{
// Iterate though the values entered by the user and HTML encode
// the values. This helps prevent malicious values from being
// stored in the data source.
for (int i = 0; i < e.Values.Count; i++)
{
if (e.Values[i] != null)
{
e.Values[i] = Server.HtmlEncode(e.Values[i].ToString());
}
}
}
void CustomerDetail_ItemUpdated(object sender,
DetailsViewUpdatedEventArgs e)
{
// Refresh the GridView control after a new record is updated
// in the DetailsView control.
CustomersView.DataBind();
}
void CustomerDetail_ItemUpdating(object sender,
DetailsViewUpdateEventArgs e)
{
// Iterate though the values entered by the user and HTML encode
// the values. This helps prevent malicious values from being
// stored in the data source.
for (int i = 0; i < e.NewValues.Count; i++)
{
if (e.NewValues[i] != null)
{
e.NewValues[i] = Server.HtmlEncode(e.NewValues[i].ToString());
}
}
}
void CustomerDetail_ItemDeleted(object sender,
DetailsViewDeletedEventArgs e)
{
// Refresh the GridView control after a new record is updated
// in the DetailsView control.
CustomersView.DataBind();
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>
DetailsView Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>
DetailsView Example</h3>
<table cellspacing="10">
<tr>
<td>
<!-- Use a GridView control in combination with -->
<!-- a DetailsView control to display master-detail -->
<!-- information. When the user selects a store from -->
<!-- GridView control, the customers//s detailed -->
<!-- information is displayed in the DetailsView -->
<!-- control. -->
<asp:GridView ID="CustomersView" DataSourceID="Customers"
AutoGenerateColumns="False"
DataKeyNames="CustomerID" runat="server">
<HeaderStyle BackColor="Blue" ForeColor="White" />
<Columns>
<asp:CommandField ShowSelectButton="True" />
<asp:BoundField DataField="ContactName"
HeaderText="ContactName" />
<asp:BoundField DataField="CompanyName"
HeaderText="CompanyName" />
</Columns>
</asp:GridView>
</td>
<td valign="top">
<asp:DetailsView ID="CustomerDetail"
DataSourceID="Details" AutoGenerateRows="false"
AutoGenerateInsertButton="true"
AutoGenerateEditButton="true"
AutoGenerateDeleteButton="true"
EmptyDataText="No records."
DataKeyNames="CustomerID" GridLines="Both"
OnItemInserted="CustomerDetail_ItemInserted"
OnItemInserting="CustomerDetail_ItemInserting"
OnItemUpdated="CustomerDetail_ItemUpdated"
OnItemUpdating="CustomerDetail_ItemUpdating"
OnItemDeleted="CustomerDetail_ItemDeleted"
runat="server">
<HeaderStyle BackColor="Navy" ForeColor="White" />
<RowStyle BackColor="White" />
<AlternatingRowStyle BackColor="LightGray" />
<EditRowStyle BackColor="LightCyan" />
<Fields>
<asp:BoundField DataField="CustomerID" HeaderText="CustomerID" ReadOnly="True" />
<asp:BoundField DataField="ContactName" HeaderText="ContactName" />
<asp:BoundField DataField="ContactTitle" HeaderText="ContactTitle" />
<asp:BoundField DataField="CompanyName" HeaderText="CompanyName" />
<asp:BoundField DataField="Address" HeaderText="Address" />
<asp:BoundField DataField="City" HeaderText="City" />
<asp:BoundField DataField="Region" HeaderText="Region" />
<asp:BoundField DataField="PostalCode" HeaderText="PostalCode" />
<asp:BoundField DataField="Country" HeaderText="Country" />
<asp:BoundField DataField="Phone" HeaderText="Phone" />
<asp:BoundField DataField="Fax" HeaderText="Fax" />
</Fields>
</asp:DetailsView>
</td>
</tr>
</table>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. -->
<!-- It is strongly recommended that each data-bound -->
<!-- control uses a separate data source control. -->
<asp:SqlDataSource ID="Customers" runat="server"
ConnectionString=
"<%$ ConnectionStrings:NorthwindConnectionString %>"
SelectCommand="SELECT [CompanyName], [ContactName], [CustomerID]
FROM [Customers]">
</asp:SqlDataSource>
<!-- Add a filter to the data source control for the -->
<!-- DetailsView control to display the details of the -->
<!-- store selected in the GridView control. -->
<asp:SqlDataSource ID="Details"
ConnectionString=
"<%$ ConnectionStrings:NorthwindConnectionString %>"
runat="server"
SelectCommand="SELECT * FROM [Customers]
WHERE ([CustomerID] = @CustomerID)"
DeleteCommand="DELETE FROM [Customers]
WHERE [CustomerID] = @CustomerID"
InsertCommand="INSERT INTO [Customers] ([CustomerID],
[CompanyName], [ContactName], [ContactTitle], [Address],
[City], [Region], [PostalCode], [Country], [Phone], [Fax])
VALUES (@CustomerID, @CompanyName, @ContactName, @ContactTitle,
@Address, @City, @Region, @PostalCode, @Country, @Phone, @Fax)"
UpdateCommand="UPDATE [Customers] SET [CompanyName] = @CompanyName,
[ContactName] = @ContactName, [ContactTitle] = @ContactTitle,
[Address] = @Address, [City] = @City, [Region] = @Region,
[PostalCode] = @PostalCode, [Country] = @Country,
[Phone] = @Phone, [Fax] = @Fax
WHERE [CustomerID] = @CustomerID">
<SelectParameters>
<asp:ControlParameter ControlID="CustomersView"
Name="CustomerID" PropertyName="SelectedValue"
Type="String" />
</SelectParameters>
<DeleteParameters>
<asp:Parameter Name="CustomerID" Type="String" />
</DeleteParameters>
<UpdateParameters>
<asp:Parameter Name="CompanyName" Type="String" />
<asp:Parameter Name="ContactName" Type="String" />
<asp:Parameter Name="ContactTitle" Type="String" />
<asp:Parameter Name="Address" Type="String" />
<asp:Parameter Name="City" Type="String" />
<asp:Parameter Name="Region" Type="String" />
<asp:Parameter Name="PostalCode" Type="String" />
<asp:Parameter Name="Country" Type="String" />
<asp:Parameter Name="Phone" Type="String" />
<asp:Parameter Name="Fax" Type="String" />
<asp:Parameter Name="CustomerID" Type="String" />
</UpdateParameters>
<InsertParameters>
<asp:Parameter Name="CustomerID" Type="String" />
<asp:Parameter Name="CompanyName" Type="String" />
<asp:Parameter Name="ContactName" Type="String" />
<asp:Parameter Name="ContactTitle" Type="String" />
<asp:Parameter Name="Address" Type="String" />
<asp:Parameter Name="City" Type="String" />
<asp:Parameter Name="Region" Type="String" />
<asp:Parameter Name="PostalCode" Type="String" />
<asp:Parameter Name="Country" Type="String" />
<asp:Parameter Name="Phone" Type="String" />
<asp:Parameter Name="Fax" Type="String" />
</InsertParameters>
</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 CustomerDetail_ItemInserted(ByVal sender As Object, _
ByVal e As DetailsViewInsertedEventArgs)
' Refresh the GridView control after a new record is inserted in
' the DetailsView control.
CustomersView.DataBind()
End Sub
Sub CustomerDetail_ItemInserting(ByVal sender As Object, _
ByVal e As DetailsViewInsertEventArgs)
' Iterate though the values entered by the user and HTML encode
' the values. This helps prevent malicious values from being
' stored in the data source.
For i As Integer = 0 To e.Values.Count - 1
If e.Values(i) IsNot Nothing Then
e.Values(i) = Server.HtmlEncode(e.Values(i).ToString())
End If
Next
End Sub
Sub CustomerDetail_ItemUpdated(ByVal sender As Object, _
ByVal e As DetailsViewUpdatedEventArgs)
' Refresh the GridView control after a new record is updated
' in the DetailsView control.
CustomersView.DataBind()
End Sub
Sub CustomerDetail_ItemUpdating(ByVal sender As Object, _
ByVal e As DetailsViewUpdateEventArgs)
' Iterate though the values entered by the user and HTML encode
' the values. This helps prevent malicious values from being
' stored in the data source.
For i As Integer = 0 To e.NewValues.Count - 1
If e.NewValues(i) IsNot Nothing Then
e.NewValues(i) = Server.HtmlEncode(e.NewValues(i).ToString())
End If
Next
End Sub
Sub CustomerDetail_ItemDeleted(ByVal sender As Object, _
ByVal e As DetailsViewDeletedEventArgs)
' Refresh the GridView control after a new record is updated
' in the DetailsView control.
CustomersView.DataBind()
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsView Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>DetailsView Example</h3>
<table cellspacing="10">
<tr>
<td>
<!-- Use a GridView control in combination with -->
<!-- a DetailsView control to display master-detail -->
<!-- information. When the user selects a store from -->
<!-- GridView control, the customers's detailed -->
<!-- information is displayed in the DetailsView -->
<!-- control. -->
<asp:GridView ID="CustomersView" DataSourceID="Customers"
AutoGenerateColumns="False"
DataKeyNames="CustomerID" runat="server">
<HeaderStyle BackColor="Blue" ForeColor="White" />
<Columns>
<asp:CommandField ShowSelectButton="True" />
<asp:BoundField DataField="ContactName"
HeaderText="ContactName" />
<asp:BoundField DataField="CompanyName"
HeaderText="CompanyName" />
</Columns>
</asp:GridView>
</td>
<td valign="top">
<asp:DetailsView ID="CustomerDetail" DataSourceID="Details"
AutoGenerateRows="false"
AutoGenerateInsertButton="true"
AutoGenerateEditButton="true"
AutoGenerateDeleteButton="true"
EmptyDataText="No records."
DataKeyNames="CustomerID" GridLines="Both"
OnItemInserted="CustomerDetail_ItemInserted"
OnItemInserting="CustomerDetail_ItemInserting"
OnItemUpdated="CustomerDetail_ItemUpdated"
OnItemUpdating="CustomerDetail_ItemUpdating"
OnItemDeleted="CustomerDetail_ItemDeleted"
runat="server">
<HeaderStyle BackColor="Navy" ForeColor="White" />
<RowStyle BackColor="White" />
<AlternatingRowStyle BackColor="LightGray" />
<EditRowStyle BackColor="LightCyan" />
<Fields>
<asp:BoundField DataField="CustomerID" HeaderText="CustomerID"
ReadOnly="True" />
<asp:BoundField DataField="ContactName" HeaderText="ContactName" />
<asp:BoundField DataField="ContactTitle" HeaderText="ContactTitle" />
<asp:BoundField DataField="CompanyName" HeaderText="CompanyName" />
<asp:BoundField DataField="Address" HeaderText="Address" />
<asp:BoundField DataField="City" HeaderText="City" />
<asp:BoundField DataField="Region" HeaderText="Region" />
<asp:BoundField DataField="PostalCode" HeaderText="PostalCode" />
<asp:BoundField DataField="Country" HeaderText="Country" />
<asp:BoundField DataField="Phone" HeaderText="Phone" />
<asp:BoundField DataField="Fax" HeaderText="Fax" />
</Fields>
</asp:DetailsView>
</td>
</tr>
</table>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the Northwind sample database. -->
<!-- It is strongly recommended that each data-bound -->
<!-- control uses a separate data source control. -->
<asp:SqlDataSource ID="Customers" runat="server"
ConnectionString=
"<%$ ConnectionStrings:NorthwindConnectionString %>"
SelectCommand="SELECT [CompanyName], [ContactName], [CustomerID]
FROM [Customers]">
</asp:SqlDataSource>
<!-- Add a filter to the data source control for the -->
<!-- DetailsView control to display the details of the -->
<!-- store selected in the GridView control. -->
<asp:SqlDataSource ID="Details"
ConnectionString=
"<%$ ConnectionStrings:NorthwindConnectionString %>"
runat="server"
SelectCommand="SELECT * FROM [Customers]
WHERE ([CustomerID] = @CustomerID)"
DeleteCommand="DELETE FROM [Customers]
WHERE [CustomerID] = @CustomerID"
InsertCommand="INSERT INTO [Customers] ([CustomerID],
[CompanyName], [ContactName], [ContactTitle], [Address],
[City], [Region], [PostalCode], [Country], [Phone], [Fax])
VALUES (@CustomerID, @CompanyName, @ContactName,
@ContactTitle, @Address, @City, @Region, @PostalCode,
@Country, @Phone, @Fax)"
UpdateCommand="UPDATE [Customers] SET
[CompanyName] = @CompanyName,
[ContactName] = @ContactName, [ContactTitle] = @ContactTitle,
[Address] = @Address, [City] = @City, [Region] = @Region,
[PostalCode] = @PostalCode, [Country] = @Country,
[Phone] = @Phone, [Fax] = @Fax
WHERE [CustomerID] = @CustomerID">
<SelectParameters>
<asp:ControlParameter ControlID="CustomersView"
Name="CustomerID" PropertyName="SelectedValue"
Type="String" />
</SelectParameters>
<DeleteParameters>
<asp:Parameter Name="CustomerID" Type="String" />
</DeleteParameters>
<UpdateParameters>
<asp:Parameter Name="CompanyName" Type="String" />
<asp:Parameter Name="ContactName" Type="String" />
<asp:Parameter Name="ContactTitle" Type="String" />
<asp:Parameter Name="Address" Type="String" />
<asp:Parameter Name="City" Type="String" />
<asp:Parameter Name="Region" Type="String" />
<asp:Parameter Name="PostalCode" Type="String" />
<asp:Parameter Name="Country" Type="String" />
<asp:Parameter Name="Phone" Type="String" />
<asp:Parameter Name="Fax" Type="String" />
<asp:Parameter Name="CustomerID" Type="String" />
</UpdateParameters>
<InsertParameters>
<asp:Parameter Name="CustomerID" Type="String" />
<asp:Parameter Name="CompanyName" Type="String" />
<asp:Parameter Name="ContactName" Type="String" />
<asp:Parameter Name="ContactTitle" Type="String" />
<asp:Parameter Name="Address" Type="String" />
<asp:Parameter Name="City" Type="String" />
<asp:Parameter Name="Region" Type="String" />
<asp:Parameter Name="PostalCode" Type="String" />
<asp:Parameter Name="Country" Type="String" />
<asp:Parameter Name="Phone" Type="String" />
<asp:Parameter Name="Fax" Type="String" />
</InsertParameters>
</asp:SqlDataSource>
</form>
</body>
</html>
Hinweise
Das ItemUpdating Ereignis wird ausgelöst, wenn auf eine Schaltfläche Aktualisieren innerhalb eines DetailsView Steuerelements geklickt wird, jedoch vor dem Updatevorgang. Dadurch können Sie einen Ereignishandler bereitstellen, der eine benutzerdefinierte Routine ausführt, z. B. das Abbrechen des Aktualisierungsvorgangs, wenn dieses Ereignis auftritt.
Ein DetailsViewUpdateEventArgs -Objekt wird an den Ereignishandler übergeben, mit dem Sie den Index des zu aktualisierenden Datensatzes bestimmen und angeben können, dass der Aktualisierungsvorgang abgebrochen werden soll. Um den Aktualisierungsvorgang abzubrechen, legen Sie die Cancel -Eigenschaft auf fest true
. Sie können bei Bedarf auch die KeysAuflistungen , OldValuesund NewValues bearbeiten, bevor die Werte an die Datenquelle übergeben werden. Eine gängige Möglichkeit, diese Sammlungen zu verwenden, besteht darin, die vom Benutzer bereitgestellten Werte html zu codieren, bevor sie in der Datenquelle gespeichert werden. Dies trägt dazu bei, Skripteinschleusungsangriffe zu verhindern.
Weitere Informationen zum Behandeln von Ereignissen finden Sie unter behandeln und Auslösen von Ereignissen.