FormViewUpdatedEventArgs.Exception Properti
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.
Mendapatkan pengecualian (jika ada) yang dinaikkan selama operasi pembaruan.
public:
property Exception ^ Exception { Exception ^ get(); };
public Exception Exception { get; }
member this.Exception : Exception
Public ReadOnly Property Exception As Exception
Nilai Properti
Objek Exception yang mewakili pengecualian yang dimunculkan selama operasi pembaruan.
Contoh
Contoh berikut menunjukkan cara menggunakan Exception properti untuk menentukan apakah pengecualian terjadi selama operasi pembaruan.
<%@ 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_ItemUpdated(Object sender, FormViewUpdatedEventArgs e)
{
// Use the Exception property to determine whether an exception
// occurred during the update operation.
if (e.Exception == null)
{
// Sometimes an error might occur that does not raise an
// exception, but prevents the update operation from
// completing. Use the AffectedRows property to determine
// whether the record was actually updated.
if (e.AffectedRows == 1)
{
// Use the Keys property to get the value of the key field.
String keyFieldValue = e.Keys["EmployeeID"].ToString();
// Display a confirmation message.
MessageLabel.Text = "Record " + keyFieldValue +
" updated successfully. ";
// Display the new and original values.
DisplayValues((OrderedDictionary)e.NewValues, (OrderedDictionary)e.OldValues);
}
else
{
// Display an error message.
MessageLabel.Text = "An error occurred during the update operation.";
// When an error occurs, keep the FormView
// control in edit mode.
e.KeepInEditMode = true;
}
}
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;
e.KeepInEditMode = true;
}
}
void DisplayValues(OrderedDictionary newValues, OrderedDictionary oldValues)
{
MessageLabel.Text += "<br/></br>";
// Iterate through the new and old values. Display the
// values on the page.
for (int i = 0; i < oldValues.Count; i++)
{
MessageLabel.Text += "Old Value=" + oldValues[i].ToString() +
", New Value=" + newValues[i].ToString() + "<br/>";
}
MessageLabel.Text += "</br>";
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FormViewUpdatedEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>FormViewUpdatedEventArgs Example</h3>
<asp:formview id="EmployeeFormView"
datasourceid="EmployeeSource"
allowpaging="true"
datakeynames="EmployeeID"
emptydatatext="No employees found."
onitemupdated="EmployeeFormView_ItemUpdated"
runat="server">
<itemtemplate>
<table>
<tr>
<td rowspan="6">
<asp:image id="EmployeeImage"
imageurl='<%# Eval("PhotoPath") %>'
alternatetext='<%# Eval("LastName") %>'
runat="server"/>
</td>
<td colspan="2">
</td>
</tr>
<tr>
<td>
<b>Name:</b>
</td>
<td>
<%# Eval("FirstName") %> <%# Eval("LastName") %>
</td>
</tr>
<tr>
<td>
<b>Title:</b>
</td>
<td>
<%# Eval("Title") %>
</td>
</tr>
<tr>
<td>
<b>Hire Date:</b>
</td>
<td>
<%# Eval("HireDate","{0:d}") %>
</td>
</tr>
<tr style="height:150" valign="top">
<td>
<b>Address:</b>
</td>
<td>
<%# Eval("Address") %><br/>
<%# Eval("City") %> <%# Eval("Region") %>
<%# Eval("PostalCode") %><br/>
<%# Eval("Country") %>
</td>
</tr>
<tr>
<td colspan="2">
<asp:linkbutton id="Edit"
text="Edit"
commandname="Edit"
runat="server"/>
</td>
</tr>
</table>
</itemtemplate>
<edititemtemplate>
<table>
<tr>
<td rowspan="6">
<asp:image id="EmployeeEditImage"
imageurl='<%# Eval("PhotoPath") %>'
alternatetext='<%# Eval("LastName") %>'
runat="server"/>
</td>
<td colspan="2">
</td>
</tr>
<tr>
<td>
<b><asp:Label runat="server"
AssociatedControlID="FirstNameUpdateTextBox"
Text="Name" />:</b>
</td>
<td>
<asp:textbox id="FirstNameUpdateTextBox"
text='<%# Bind("FirstName") %>'
accesskey="n" tabindex="1" runat="server"/>
<asp:textbox id="LastNameUpdateTextBox"
text='<%# Bind("LastName") %>'
accesskey="l" tabindex="2" runat="server"/>
</td>
</tr>
<tr>
<td>
<b><asp:Label runat="server"
AssociatedControlID="TitleUpdateTextBox"
Text="Title" />:</b>
</td>
<td>
<asp:textbox id="TitleUpdateTextBox"
text='<%# Bind("Title") %>'
accesskey="t" tabindex="3" runat="server"/>
</td>
</tr>
<tr>
<b><asp:Label runat="server"
AssociatedControlID="HireDateUpdateTextBox"
Text="Hire Date" />:</b>
<td>
<asp:textbox id="HireDateUpdateTextBox"
text='<%# Bind("HireDate", "{0:d}") %>'
accesskey="h" tabindex="4" runat="server" />
</td>
</tr>
<tr style="height:150" valign="top">
<td>
<b><asp:Label runat="server"
AssociatedControlID="AddressUpdateTextBox"
Text="Address" />:</b>
</td>
<td>
<asp:textbox id="AddressUpdateTextBox"
text='<%# Bind("Address") %>'
accesskey="a" tabindex="5" runat="server"/>
<br/>
<asp:textbox id="CityUpdateTextBox"
text='<%# Bind("City") %>'
accesskey="c" tabindex="6" runat="server"/>
<asp:textbox id="RegionUpdateTextBox"
text='<%# Bind("Region") %>'
width="40"
accesskey="r" tabindex="7" runat="server"/>
<asp:textbox id="PostalCodeUpdateTextBox"
text='<%# Bind("PostalCode") %>'
width="60"
accesskey="p" tabindex="8" runat="server"/>
<br/>
<asp:textbox id="CountryUpdateTextBox"
text='<%# Bind("Country") %>'
accesskey="u" tabindex="9" runat="server"/>
</td>
</tr>
<tr>
<td colspan="2">
<asp:linkbutton id="UpdateButton"
text="Update" tabindex="10"
commandname="Update"
runat="server"/>
<asp:linkbutton id="CancelButton"
text="Cancel" tabindex="11"
commandname="Cancel"
runat="server"/>
</td>
</tr>
</table>
</edititemtemplate>
</asp:formview>
<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="EmployeeSource"
selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [Address], [City], [Region], [PostalCode], [Country], [HireDate], [PhotoPath] From [Employees]"
updatecommand="Update [Employees] Set [LastName]=@LastName, [FirstName]=@FirstName, [Title]=@Title, [Address]=@Address, [City]=@City, [Region]=@Region, [PostalCode]=@PostalCode, [Country]=@Country 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_ItemUpdated(ByVal sender As Object, ByVal e As FormViewUpdatedEventArgs) Handles EmployeeFormView.ItemUpdated
' Use the Exception property to determine whether an exception
' occurred during the update operation.
If e.Exception Is Nothing Then
' Sometimes an error might occur that does not raise an
' exception, but prevents the update operation from
' completing. Use the AffectedRows property to determine
' whether the record was actually updated.
If e.AffectedRows = 1 Then
' Use the Keys property to get the value of the key field.
Dim keyFieldValue As String = e.Keys("EmployeeID").ToString()
' Display a confirmation message.
MessageLabel.Text = "Record " & keyFieldValue & _
" updated successfully. "
' Display the new and original values.
DisplayValues(CType(e.NewValues, OrderedDictionary), CType(e.OldValues, OrderedDictionary))
Else
' Display an error message.
MessageLabel.Text = "An error occurred during the update operation."
' When an error occurs, keep the FormView
' control in edit mode.
e.KeepInEditMode = True
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
e.KeepInEditMode = True
End If
End Sub
Sub DisplayValues(ByVal newValues As OrderedDictionary, ByVal oldValues As OrderedDictionary)
MessageLabel.Text &= "<br/></br>"
' Iterate through the new and old values. Display the
' values on the page.
Dim i As Integer
For i = 0 To oldValues.Count - 1
MessageLabel.Text &= "Old Value=" & oldValues(i).ToString() & _
", New Value=" & newValues(i).ToString() & "<br/>"
Next
MessageLabel.Text &= "</br>"
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FormViewUpdatedEventArgs Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>FormViewUpdatedEventArgs Example</h3>
<asp:formview id="EmployeeFormView"
datasourceid="EmployeeSource"
allowpaging="true"
datakeynames="EmployeeID"
emptydatatext="No employees found."
runat="server">
<itemtemplate>
<table>
<tr>
<td rowspan="6">
<asp:image id="EmployeeImage"
imageurl='<%# Eval("PhotoPath") %>'
alternatetext='<%# Eval("LastName") %>'
runat="server"/>
</td>
<td colspan="2">
</td>
</tr>
<tr>
<td>
<b>Name:</b>
</td>
<td>
<%# Eval("FirstName") %> <%# Eval("LastName") %>
</td>
</tr>
<tr>
<td>
<b>Title:</b>
</td>
<td>
<%# Eval("Title") %>
</td>
</tr>
<tr>
<td>
<b>Hire Date:</b>
</td>
<td>
<%# Eval("HireDate","{0:d}") %>
</td>
</tr>
<tr style="height:150" valign="top">
<td>
<b>Address:</b>
</td>
<td>
<%# Eval("Address") %><br/>
<%# Eval("City") %> <%# Eval("Region") %>
<%# Eval("PostalCode") %><br/>
<%# Eval("Country") %>
</td>
</tr>
<tr>
<td colspan="2">
<asp:linkbutton id="Edit"
text="Edit"
commandname="Edit"
runat="server"/>
</td>
</tr>
</table>
</itemtemplate>
<edititemtemplate>
<table>
<tr>
<td rowspan="6">
<asp:image id="EmployeeEditImage"
imageurl='<%# Eval("PhotoPath") %>'
alternatetext='<%# Eval("LastName") %>'
runat="server"/>
</td>
<td colspan="2">
</td>
</tr>
<tr>
<td>
<b><asp:Label runat="server"
AssociatedControlID="FirstNameUpdateTextBox"
Text="Name" />:</b>
</td>
<td>
<asp:textbox id="FirstNameUpdateTextBox"
text='<%# Bind("FirstName") %>'
accesskey="n" tabindex="1" runat="server"/>
<asp:textbox id="LastNameUpdateTextBox"
text='<%# Bind("LastName") %>'
accesskey="l" tabindex="2" runat="server"/>
</td>
</tr>
<tr>
<td>
<b><asp:Label runat="server"
AssociatedControlID="TitleUpdateTextBox"
Text="Title" />:</b>
</td>
<td>
<asp:textbox id="TitleUpdateTextBox"
text='<%# Bind("Title") %>'
accesskey="t" tabindex="3" runat="server"/>
</td>
</tr>
<tr>
<b><asp:Label runat="server"
AssociatedControlID="HireDateUpdateTextBox"
Text="Hire Date" />:</b>
<td>
<asp:textbox id="HireDateUpdateTextBox"
text='<%# Bind("HireDate", "{0:d}") %>'
accesskey="h" tabindex="4" runat="server" />
</td>
</tr>
<tr style="height:150" valign="top">
<td>
<b><asp:Label runat="server"
AssociatedControlID="AddressUpdateTextBox"
Text="Address" />:</b>
</td>
<td>
<asp:textbox id="AddressUpdateTextBox"
text='<%# Bind("Address") %>'
accesskey="a" tabindex="5" runat="server"/>
<br/>
<asp:textbox id="CityUpdateTextBox"
text='<%# Bind("City") %>'
accesskey="c" tabindex="6" runat="server"/>
<asp:textbox id="RegionUpdateTextBox"
text='<%# Bind("Region") %>'
width="40"
accesskey="r" tabindex="7" runat="server"/>
<asp:textbox id="PostalCodeUpdateTextBox"
text='<%# Bind("PostalCode") %>'
width="60"
accesskey="p" tabindex="8" runat="server"/>
<br/>
<asp:textbox id="CountryUpdateTextBox"
text='<%# Bind("Country") %>'
accesskey="u" tabindex="9" runat="server"/>
</td>
</tr>
<tr>
<td colspan="2">
<asp:linkbutton id="UpdateButton"
text="Update" tabindex="10"
commandname="Update"
runat="server"/>
<asp:linkbutton id="CancelButton"
text="Cancel" tabindex="11"
commandname="Cancel"
runat="server"/>
</td>
</tr>
</table>
</edititemtemplate>
</asp:formview>
<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="EmployeeSource"
selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [Address], [City], [Region], [PostalCode], [Country], [HireDate], [PhotoPath] From [Employees]"
updatecommand="Update [Employees] Set [LastName]=@LastName, [FirstName]=@FirstName, [Title]=@Title, [Address]=@Address, [City]=@City, [Region]=@Region, [PostalCode]=@PostalCode, [Country]=@Country Where [EmployeeID]=@EmployeeID"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Keterangan
Exception Gunakan properti untuk menentukan pengecualian (jika ada) yang dinaikkan selama operasi pembaruan. Jika tidak ada pengecualian yang dimunculkan, properti ini akan mengembalikan null.
Nota
Jika pengecualian dimunculkan dan Anda memutuskan untuk menangani pengecualian di penanganan aktivitas, pastikan untuk mengatur ExceptionHandled properti ke true; jika tidak, pengecualian dilemparkan lagi oleh FormView kontrol.