ListViewDeletedEventArgs.Keys Propriété
Définition
Important
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Obtient la ou les clés de l'élément supprimé.
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 IOrderedDictionaryValeur de propriété
Clé(s) de l'élément supprimé.
Exemples
L’exemple suivant montre comment utiliser la Keys propriété pour accéder aux valeurs des champs de clé d’un élément supprimé.
<%@ 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 ContactsListView_ItemDeleted(Object sender, ListViewDeletedEventArgs e)
{
// Display the value 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 value 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>ListViewDeletedEventArgs Keys and Values Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>ListViewDeletedEventArgs Keys and Values Example</h3>
<asp:Label ID="Message"
ForeColor="Red"
runat="server"/>
<br/>
<asp:ListView ID="ContactsListView"
DataSourceID="ContactsDataSource"
DataKeyNames="ContactID"
OnItemDeleted="ContactsListView_ItemDeleted"
runat="server">
<LayoutTemplate>
<table cellpadding="2" runat="server" id="tblContacts" width="640px">
<tr id="itemPlaceholder" runat="server"></tr>
</table>
<asp:DataPager runat="server" ID="PeopleDataPager" PageSize="12">
<Fields>
<asp:NextPreviousPagerField
ShowFirstPageButton="true" ShowLastPageButton="true"
FirstPageText="|<< " LastPageText=" >>|"
NextPageText=" > " PreviousPageText=" < " />
</Fields>
</asp:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr runat="server">
<td valign="top">
<asp:Label ID="FirstNameLabel" runat="server" Text='<%#Bind("FirstName") %>' />
<asp:Label ID="LastNameLabel" runat="server" Text='<%#Bind("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailLabel" runat="server" Text='<%#Bind("EmailAddress") %>' />
</td>
<td>
<asp:LinkButton ID="DeleteButton" runat="server"
CommandName="Delete"
Text="Delete"
OnClientClick="return confirm('Are you sure?');" />
</td>
</tr>
</ItemTemplate>
</asp:ListView>
<br/><br />
<asp:Label ID="KeysMessageLabel"
ForeColor="Red"
runat="server"/>
<br/>
<asp:Label ID="ValuesMessageLabel"
ForeColor="Red"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the AdventureWorks sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:SqlDataSource ID="ContactsDataSource" runat="server"
ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
SelectCommand="SELECT [ContactID], [FirstName], [LastName], [EmailAddress] FROM Person.Contact"
DeleteCommand="DELETE FROM Person.Contact WHERE [ContactID] = @ContactID">
<DeleteParameters>
<asp:Parameter Name="ContactID" Type="Int32" />
</DeleteParameters>
</asp:SqlDataSource>
</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 ContactsListView_ItemDeleted(sender As Object, e As ListViewDeletedEventArgs)
' Display the value of the key fields in the Keys property.
KeysMessageLabel.Text = _
"The key fields for the deleted record are: <br/>"
For Each entry As DictionaryEntry In e.Keys
DisplayValue(entry, KeysMessageLabel)
Next
' Display the value of the non-key fields in the Values
' property.
ValuesMessageLabel.Text = _
"The non-key fields for the deleted record are: <br/>"
For Each entry As DictionaryEntry In e.Values
DisplayValue(entry, ValuesMessageLabel)
Next
End Sub
Sub DisplayValue(entry As DictionaryEntry, 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
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 id="Head1" runat="server">
<title>ListViewDeletedEventArgs Keys and Values Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>ListViewDeletedEventArgs Keys and Values Example</h3>
<asp:Label ID="Message"
ForeColor="Red"
runat="server"/>
<br/>
<asp:ListView ID="ContactsListView"
DataSourceID="ContactsDataSource"
DataKeyNames="ContactID"
OnItemDeleted="ContactsListView_ItemDeleted"
runat="server">
<LayoutTemplate>
<table cellpadding="2" runat="server" id="tblContacts" width="640px">
<tr id="itemPlaceholder" runat="server"></tr>
</table>
<asp:DataPager runat="server" ID="PeopleDataPager" PageSize="12">
<Fields>
<asp:NextPreviousPagerField
ShowFirstPageButton="true" ShowLastPageButton="true"
FirstPageText="|<< " LastPageText=" >>|"
NextPageText=" > " PreviousPageText=" < " />
</Fields>
</asp:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr runat="server">
<td valign="top">
<asp:Label ID="FirstNameLabel" runat="server" Text='<%#Bind("FirstName") %>' />
<asp:Label ID="LastNameLabel" runat="server" Text='<%#Bind("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailLabel" runat="server" Text='<%#Bind("EmailAddress") %>' />
</td>
<td>
<asp:LinkButton ID="DeleteButton" runat="server"
CommandName="Delete"
Text="Delete"
OnClientClick="return confirm('Are you sure?');" />
</td>
</tr>
</ItemTemplate>
</asp:ListView>
<br/><br />
<asp:Label ID="KeysMessageLabel"
ForeColor="Red"
runat="server"/>
<br/>
<asp:Label ID="ValuesMessageLabel"
ForeColor="Red"
runat="server"/>
<!-- This example uses Microsoft SQL Server and connects -->
<!-- to the AdventureWorks sample database. Use an ASP.NET -->
<!-- expression to retrieve the connection string value -->
<!-- from the Web.config file. -->
<asp:SqlDataSource ID="ContactsDataSource" runat="server"
ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
SelectCommand="SELECT [ContactID], [FirstName], [LastName], [EmailAddress] FROM Person.Contact"
DeleteCommand="DELETE FROM Person.Contact WHERE [ContactID] = @ContactID">
<DeleteParameters>
<asp:Parameter Name="ContactID" Type="Int32" />
</DeleteParameters>
</asp:SqlDataSource>
</form>
</body>
</html>
Remarques
Utilisez la Keys propriété pour accéder aux valeurs des champs de clé (comme spécifié par la ListView.DataKeyNames propriété) pour un élément supprimé. Par exemple, vous pouvez utiliser ces valeurs pour conserver un journal des éléments supprimés.
Notes
Cette propriété contient uniquement les champs de clé. Pour accéder aux champs non clés, utilisez la Values propriété .
La propriété Keys retourne un objet qui implémente l'interface IOrderedDictionary. L’objet contient des DictionaryEntry objets qui représentent les champs clés de l’élément supprimé.
S’applique à
Voir aussi
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