DetailsViewUpdatedEventHandler Delegate
Represents the method that handles the ItemUpdated event of a DetailsView control. This class cannot be inherited.
Assembly: System.Web (in System.Web.dll)
Public Delegate Sub DetailsViewUpdatedEventHandler ( sender As Object, e As DetailsViewUpdatedEventArgs )
Parameters
- sender
-
Type:
System.Object
The source of the event.
- e
-
Type:
System.Web.UI.WebControls.DetailsViewUpdatedEventArgs
A DetailsViewUpdatedEventArgs that contains the event data.
The DetailsView control raises the ItemUpdated event when an Update button (a button with its CommandName property set to "Update") within the control is clicked, but after the DetailsView control updates the record. This allows you to provide an event handler that performs a custom routine, such as checking the results of an update operation, whenever this event occurs.
When you create a DetailsViewUpdatedEventHandler 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 NIB: Events and Delegates.
The following code example demonstrates how to programmatically add a DetailsViewUpdatedEventHandler delegate to the ItemUpdated event of a DetailsView control.
<%@ 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(sender As Object, 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.AutoGenerateEditButton = True customerDetailsView.AllowPaging = True customerDetailsView.PagerSettings.Position = PagerPosition.Bottom Dim keyArray() As String = {"CustomerID"} customerDetailsView.DataKeyNames = keyArray ' Programmatically register the event-handling methods ' for the DetailsView control. AddHandler customerDetailsView.ItemUpdated, _ AddressOf CustomerDetailsView_ItemUpdated ' Add the DetailsView object to the Controls collection ' of the PlaceHolder control. DetailsViewPlaceHolder.Controls.Add(customerDetailsView) End Sub Sub CustomerDetailsView_ItemUpdated(ByVal sender As Object, _ ByVal e As DetailsViewUpdatedEventArgs) ' Use the Exception property to determine whether an exception ' occurred during the insert operation. If e.Exception Is Nothing Then ' Use the Values property to get the value entered by ' the user for the CompanyName field. Dim keyFieldValue As String = e.Keys("CustomerID").ToString() ' Display a confirmation message. MessageLabel.Text = "Record " & keyFieldValue & _ " updated successfully. " ' Display the old and new values. DisplayValues(e) If e.AffectedRows = 1 Then MessageLabel.Text &= e.AffectedRows.ToString() & _ " record updated." Else MessageLabel.Text &= e.AffectedRows.ToString() & _ " records updated." End If Else ' Insert the code to handle the exception. MessageLabel.Text = e.Exception.Message ' Use the ExceptionHandled property to indicate that the ' exception is already handled. e.ExceptionHandled = True ' When an exception occurs, keep the DetailsView ' control in edit mode. e.KeepInEditMode = True End If End Sub Sub DisplayValues(ByVal e As DetailsViewUpdatedEventArgs) MessageLabel.Text &= "<br/></br>" ' Iterate through the OldValue and NewValues ' properties and display the values. Dim i As Integer For i = 0 To e.OldValues.Count - 1 MessageLabel.Text &= "Old Value=" & e.OldValues(i).ToString() & _ ", New Value=" & e.NewValues(i).ToString() & "<br/>" Next MessageLabel.Text &= "</br>" End Sub </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>DetailsViewUpdatedEventHandler Example</title> </head> <body> <form id="form1" runat="server"> <h3>DetailsViewUpdatedEventHandler 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]" updatecommand="Update [Customers] Set [CompanyName]=@CompanyName, [Address]=@Address, [City]=@City, [PostalCode]=@PostalCode, [Country]=@Country Where [CustomerID]=@CustomerID" connectionstring= "<%$ ConnectionStrings:NorthWindConnectionString%>" runat="server"/> </form> </body> </html>
The following code example demonstrates how to declaratively add a DetailsViewUpdatedEventHandler delegate to the ItemUpdated event of a DetailsView control.
<%@ 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_ItemUpdated(ByVal sender As Object, ByVal e As DetailsViewUpdatedEventArgs) Handles CustomerDetailsView.ItemUpdated ' Use the Exception property to determine whether an exception ' occurred during the insert operation. If e.Exception Is Nothing Then ' Use the Values property to get the value entered by ' the user for the CompanyName field. Dim keyFieldValue As String = e.Keys("CustomerID").ToString() ' Display a confirmation message. MessageLabel.Text = "Record " & keyFieldValue & _ " updated successfully. " ' Display the old and new values. DisplayValues(e) If e.AffectedRows = 1 Then MessageLabel.Text &= e.AffectedRows.ToString() & _ " record updated." Else MessageLabel.Text &= e.AffectedRows.ToString() & _ " records updated." End If Else ' Insert the code to handle the exception. MessageLabel.Text = e.Exception.Message ' Use the ExceptionHandled property to indicate that the ' exception is already handled. e.ExceptionHandled = True ' When an exception occurs, keep the DetailsView ' control in edit mode. e.KeepInEditMode = True End If End Sub Sub DisplayValues(ByVal e As DetailsViewUpdatedEventArgs) MessageLabel.Text &= "<br/></br>" ' Iterate through the OldValue and NewValues ' properties and display the values. Dim i As Integer For i = 0 To e.OldValues.Count - 1 MessageLabel.Text &= "Old Value=" & e.OldValues(i).ToString() & _ ", New Value=" & e.NewValues(i).ToString() & "<br/>" Next MessageLabel.Text &= "</br>" End Sub </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>DetailsViewUpdatedEvent Handler Example</title> </head> <body> <form id="form1" runat="server"> <h3>DetailsViewUpdatedEvent Handler Example</h3> <asp:detailsview id="CustomerDetailsView" datasourceid="DetailsViewSource" autogeneraterows="true" autogenerateeditbutton="true" allowpaging="true" datakeynames="CustomerID" runat="server"> <pagersettings position="Bottom"/> </asp:detailsview> <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]" updatecommand="Update [Customers] Set [CompanyName]=@CompanyName, [Address]=@Address, [City]=@City, [PostalCode]=@PostalCode, [Country]=@Country Where [CustomerID]=@CustomerID" connectionstring= "<%$ ConnectionStrings:NorthWindConnectionString%>" runat="server"/> </form> </body> </html>
Available since 2.0