FormViewDeletedEventArgs.Keys 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 kamus yang diurutkan dari pasangan nama/nilai bidang kunci untuk rekaman yang dihapus.
public:
property System::Collections::Specialized::IOrderedDictionary ^ Keys { System::Collections::Specialized::IOrderedDictionary ^ get(); };public System.Collections.Specialized.IOrderedDictionary Keys { get; }member this.Keys : System.Collections.Specialized.IOrderedDictionaryPublic ReadOnly Property Keys As IOrderedDictionaryNilai Properti
Yang OrderedDictionary berisi pasangan nama/nilai bidang kunci untuk rekaman yang dihapus.
Contoh
Contoh berikut menunjukkan cara menggunakan Keys properti untuk mengakses nilai bidang kunci untuk rekaman yang dihapus.
<%@ 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)
{
// Display the values of the key fields in the Keys property.
KeysMessageLabel.Text =
"The key fields for the deleted record are: <br/>";
foreach (DictionaryEntry entry in e.Keys)
{
DisplayValue(entry, KeysMessageLabel);
}
// Display the values of the non-key fields in the Values
// property.
ValuesMessageLabel.Text =
"The non-key fields for the deleted record are: <br/>";
foreach (DictionaryEntry entry in e.Values)
{
DisplayValue(entry, ValuesMessageLabel);
}
}
void DisplayValue(DictionaryEntry entry, Label displayLabel)
{
// Display the field name contained in the DictionaryEntry object.
if (entry.Key != null)
{
displayLabel.Text += "Name=" + entry.Key.ToString() + ", ";
}
else
{
displayLabel.Text += "Name=null, ";
}
// Display the field value contained in the DictionaryEntry object.
if (entry.Value != null)
{
displayLabel.Text += "Value=" + entry.Value.ToString() + "<br/>";
}
else
{
displayLabel.Text += "Value=null<br/>";
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FormViewDeletedEventArgs Keys and Values Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>FormViewDeletedEventArgs Keys and Values 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>
<asp:label id="FirstNameLabel"
text='<%#Bind("FirstName")%>'
font-bold="true"
runat="server"/>
<asp:label id="LastNameLabel"
text='<%#Bind("LastName")%>'
font-bold="true"
runat="server"/>
<br/>
<asp:label id="TitleLabel"
text='<%#Bind("Title")%>'
runat="server"/>
</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="KeysMessageLabel"
forecolor="Red"
runat="server"/>
<br/><br/>
<asp:label id="ValuesMessageLabel"
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
Dim entry As DictionaryEntry
' Display the values of the key fields in the Keys property.
KeysMessageLabel.Text = _
"The key fields for the deleted record are: <br/>"
' In Visual Basic, you cannot iterate through the DictionaryEntry objects
' in the Keys property directly. Use the CopyTo method to
' copy the objects to an array first.
Dim keysArray(e.Keys.Count - 1) As DictionaryEntry
e.Keys.CopyTo(keysArray, 0)
' Iterate through the array and display its values.
For Each entry In keysArray
DisplayValue(entry, KeysMessageLabel)
Next
' Display the values of the non-key fields in the Values
' property.
ValuesMessageLabel.Text = _
"The non-key fields for the deleted record are: <br/>"
Dim valuesArray(e.Values.Count - 1) As DictionaryEntry
e.Values.CopyTo(valuesArray, 0)
For Each entry In valuesArray
DisplayValue(entry, ValuesMessageLabel)
Next
End Sub
Sub DisplayValue(ByVal entry As DictionaryEntry, ByVal displayLabel As Label)
' Display the field name contained in the DictionaryEntry object.
If entry.Key IsNot Nothing Then
displayLabel.Text &= "Name=" & entry.Key.ToString() & ", "
Else
displayLabel.Text &= "Name=null, "
End If
' Display the field value contained in the DictionaryEntry object.
If entry.Value IsNot Nothing Then
displayLabel.Text &= "Value=" & entry.Value.ToString() & "<br/>"
Else
displayLabel.Text &= "Value=null<br/>"
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>FormViewDeletedEventArgs Keys and Values Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>FormViewDeletedEventArgs Keys and Values 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>
<asp:label id="FirstNameLabel"
text='<%#Bind("FirstName")%>'
font-bold="true"
runat="server"/>
<asp:label id="LastNameLabel"
text='<%#Bind("LastName")%>'
font-bold="true"
runat="server"/>
<br/>
<asp:label id="TitleLabel"
text='<%#Bind("Title")%>'
runat="server"/>
</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="KeysMessageLabel"
forecolor="Red"
runat="server"/>
<br/><br/>
<asp:label id="ValuesMessageLabel"
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
Properti Keys berisi nilai bidang kunci yang tercantum dalam DataKeyNames properti FormView kontrol. Keys Gunakan properti untuk mengakses nilai bidang kunci (seperti yang ditentukan oleh DataKeyNames properti) untuk rekaman yang dihapus. Misalnya, Anda dapat menggunakan nilai-nilai ini untuk menyimpan log rekaman yang dihapus.
Nota
Properti ini hanya berisi bidang kunci yang ditentukan dalam DataKeyNames properti . Untuk mengakses bidang non-kunci, gunakan Values properti .
Properti Keys mengembalikan OrderedDictionary objek yang mengimplementasikan System.Collections.Specialized.IOrderedDictionary antarmuka. Objek OrderedDictionary berisi System.Collections.DictionaryEntry objek yang mewakili bidang kunci rekaman yang dihapus. Untuk mengakses nama bidang, gunakan Keys properti OrderedDictionary objek. Demikian pula, Anda dapat mengakses nilai bidang dengan menggunakan Values properti .
Nota
Sebagai pintasan, Anda juga dapat menggunakan pengindeks OrderedDictionary objek untuk mengakses nilai bidang kunci. Keuntungan dalam menggunakan pengindeks adalah mengembalikan nilai bidang kunci secara langsung. Kontrol sumber data yang mengandalkan urutan bidang (seperti AccessDataSource) hanya dapat mengakses nilai bidang kunci berdasarkan indeks.
