FormViewDeletedEventArgs.ExceptionHandled Eigenschap
Definitie
Belangrijk
Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.
Hiermee wordt een waarde opgehaald of ingesteld die aangeeft of er een uitzondering is gegenereerd tijdens de verwijderbewerking in de gebeurtenis-handler.
public:
property bool ExceptionHandled { bool get(); void set(bool value); };public bool ExceptionHandled { get; set; }member this.ExceptionHandled : bool with get, setPublic Property ExceptionHandled As BooleanWaarde van eigenschap
true als de uitzondering is verwerkt in de gebeurtenis-handler; anders, false. De standaardwaarde is false.
Voorbeelden
In het volgende voorbeeld ziet u hoe u de ExceptionHandled eigenschap gebruikt om aan te geven dat de uitzondering is verwerkt in de gebeurtenis-handler.
<%@ 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 EmployeeFormView_ItemDeleted(Object sender, FormViewDeletedEventArgs e)
{
// Use the Exception property to determine whether an exception
// occurred during the delete operation.
if (e.Exception == null)
{
// Use the AffectedRows property to determine whether the
// record was deleted. Sometimes an error might occur that
// does not raise an exception, but prevents the delete
// operation from completing.
if (e.AffectedRows == 1)
{
MessageLabel.Text = "Record deleted successfully.";
}
else
{
MessageLabel.Text = "An error occurred during the delete operation.";
}
}
else
{
// Insert the code to handle the exception.
MessageLabel.Text = e.Exception.Message;
// Use the ExceptionHandled property to indicate that the
// exception has already been handled.
e.ExceptionHandled = true;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FormViewDeletedEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>FormViewDeletedEventArgs Example</h3>
<asp:formview id="EmployeeFormView"
datasourceid="EmployeeSource"
allowpaging="true"
datakeynames="EmployeeID"
onitemdeleted="EmployeeFormView_ItemDeleted"
runat="server">
<itemtemplate>
<table>
<tr>
<td>
<asp:image id="EmployeeImage"
imageurl='<%# Eval("PhotoPath") %>'
alternatetext='<%# Eval("LastName") %>'
runat="server"/>
</td>
<td>
<h3><%# Eval("FirstName") %> <%# Eval("LastName") %></h3>
<%# Eval("Title") %>
</td>
</tr>
<tr>
<td colspan="2">
<asp:button id="DeleteButton"
text="Delete Record"
commandname="Delete"
runat="server" />
</td>
</tr>
</table>
</itemtemplate>
</asp:formview>
<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="EmployeeSource"
selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
deletecommand="Delete [Employees] Where [EmployeeID]=@EmployeeID"
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 EmployeeFormView_ItemDeleted(ByVal sender As Object, ByVal e As FormViewDeletedEventArgs) Handles EmployeeFormView.ItemDeleted
' Use the Exception property to determine whether an exception
' occurred during the delete operation.
If e.Exception Is Nothing Then
' Use the AffectedRows property to determine whether the
' record was deleted. Sometimes an error might occur that
' does not raise an exception, but prevents the delete
' operation from completing.
If e.AffectedRows = 1 Then
MessageLabel.Text = "Record deleted successfully."
Else
MessageLabel.Text = "An error occurred during the delete operation."
End If
Else
' Insert the code to handle the exception.
MessageLabel.Text = e.Exception.Message
' Use the ExceptionHandled property to indicate that the
' exception has already been handled.
e.ExceptionHandled = True
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FormViewDeletedEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>FormViewDeletedEventArgs Example</h3>
<asp:formview id="EmployeeFormView"
datasourceid="EmployeeSource"
allowpaging="true"
datakeynames="EmployeeID"
runat="server">
<itemtemplate>
<table>
<tr>
<td>
<asp:image id="EmployeeImage"
imageurl='<%# Eval("PhotoPath") %>'
alternatetext='<%# Eval("LastName") %>'
runat="server"/>
</td>
<td>
<h3><%# Eval("FirstName") %> <%# Eval("LastName") %></h3>
<%# Eval("Title") %>
</td>
</tr>
<tr>
<td colspan="2">
<asp:button id="DeleteButton"
text="Delete Record"
commandname="Delete"
runat="server" />
</td>
</tr>
</table>
</itemtemplate>
</asp:formview>
<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="EmployeeSource"
selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
deletecommand="Delete [Employees] Where [EmployeeID]=@EmployeeID"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Opmerkingen
Wanneer er een uitzondering optreedt tijdens de verwijderbewerking, gebruikt u de ExceptionHandled eigenschap om aan te geven of de uitzondering is verwerkt in de gebeurtenis-handler. Wanneer deze eigenschap is ingesteld trueop, wordt de uitzondering beschouwd als afgehandeld en wordt deze niet opnieuw gegenereerd. Als deze eigenschap is ingesteld op false, wordt de uitzondering opnieuw gegenereerd door het FormView besturingselement. Gebruik de Exception eigenschap om te bepalen welke uitzondering is gegenereerd.
