FormView.ItemDeleted Kejadian
Definisi
Penting
Beberapa informasi terkait produk prarilis yang dapat diubah secara signifikan sebelum dirilis. Microsoft tidak memberikan jaminan, tersirat maupun tersurat, sehubungan dengan informasi yang diberikan di sini.
Terjadi saat tombol Hapus dalam FormView kontrol diklik, tetapi setelah operasi hapus.
public:
event System::Web::UI::WebControls::FormViewDeletedEventHandler ^ ItemDeleted;
public event System.Web.UI.WebControls.FormViewDeletedEventHandler ItemDeleted;
member this.ItemDeleted : System.Web.UI.WebControls.FormViewDeletedEventHandler
Public Custom Event ItemDeleted As FormViewDeletedEventHandler
Jenis Acara
Contoh
Contoh berikut menunjukkan cara menggunakan ItemDeleted peristiwa untuk menentukan apakah pengecualian terjadi selama operasi penghapusan.
<%@ 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>
Keterangan
FormView Kontrol menaikkan ItemDeleted peristiwa saat tombol Hapus (tombol dengan propertinya CommandName
diatur ke "Hapus") di dalam kontrol diklik, tetapi setelah FormView kontrol menghapus rekaman. Ini memungkinkan Anda untuk menyediakan metode penanganan peristiwa yang melakukan rutinitas kustom, seperti memeriksa hasil operasi penghapusan, setiap kali peristiwa ini terjadi.
Objek FormViewDeletedEventArgs diteruskan ke metode penanganan peristiwa, yang memungkinkan Anda menentukan jumlah rekaman yang terpengaruh dan pengecualian apa pun yang mungkin telah terjadi. Untuk menentukan jumlah rekaman yang terpengaruh oleh operasi penghapusan, gunakan AffectedRows properti . Exception Gunakan properti untuk menentukan apakah ada pengecualian yang terjadi. Anda juga dapat menunjukkan apakah pengecualian ditangani dalam metode penanganan peristiwa dengan mengatur ExceptionHandled properti . Jika Anda ingin mengakses pasangan nama/nilai bidang kunci dan bidang non-kunci dari rekaman yang dihapus, gunakan Keys properti dan Values .
Untuk informasi selengkapnya tentang cara menangani peristiwa, lihat Menangani dan Menaikkan Peristiwa.