ListView.DeleteItem(Int32) Methode
Definition
Wichtig
Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.
Löscht den Datensatz am angegebenen Index aus der Datenquelle.
public:
virtual void DeleteItem(int itemIndex);public virtual void DeleteItem (int itemIndex);abstract member DeleteItem : int -> unit
override this.DeleteItem : int -> unitPublic Overridable Sub DeleteItem (itemIndex As Integer)Parameter
- itemIndex
- Int32
Der Index des zu löschenden Elements.
Ausnahmen
itemIndex ist kleiner als 0.
- oder -
Der Wert des DataSourceView-Objekts, das dem ListView-Steuerelement zugeordnet ist, ist null.
Beispiele
Das folgende Beispiel zeigt, wie Sie die DeleteItem -Methode verwenden, um das ausgewählte Element in einem ListView Steuerelement programmgesteuert aus der Datenquelle zu löschen.
<%@ 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">
// <Snippet2>
protected void DeleteButton_Click(object sender, EventArgs e)
{
//Check if an item is selected to delete it.
if (ContactsListView.SelectedIndex >= 0)
ContactsListView.DeleteItem(ContactsListView.SelectedIndex);
else
Message.Text = "No contact was selected.";
}
// </Snippet2>
protected void ContactsListView_ItemDeleted(object sender, ListViewDeletedEventArgs e)
{
//Check if an exception occurred to display an error message.
if (e.Exception != null)
{
Message.Text = "An exception occurred deleting the contact.";
e.ExceptionHandled = true;
}
else
{
// Clear the selected index.
ContactsListView.SelectedIndex = -1;
}
}
protected void ContactsListView_PagePropertiesChanging(object sender,
PagePropertiesChangingEventArgs e)
{
//Clear the selected index.
ContactsListView.SelectedIndex = -1;
}
protected void Page_Load(object sender, EventArgs e)
{
//Clear the message label.
Message.Text = "";
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>ListView DeleteItem Example</title>
<style type="text/css">
body
{
font-size: 10pt;
font-family: Trebuchet MS, Arial, Tahoma;
text-align:center;
}
.item { background-color: #E0FFFF }
.selectedItem { background-color: #B0E0E6 }
</style>
</head>
<body>
<form id="form1" runat="server">
<h3>ListView DeleteItem Example</h3>
<asp:ListView ID="ContactsListView"
DataSourceID="ContactsDataSource"
DataKeyNames="ContactID"
OnItemDeleted="ContactsListView_ItemDeleted"
OnPagePropertiesChanging="ContactsListView_PagePropertiesChanging"
runat="server" >
<LayoutTemplate>
<table cellpadding="2" width="640px" id="tblProducts" runat="server">
<tr runat="server">
<th runat="server"> </th>
<th runat="server">ID</th>
<th runat="server">Account Number</th>
<th runat="server">LastName</th>
<th runat="server">Preferred Vendor</th>
</tr>
<tr runat="server" id="itemPlaceholder" />
</table>
<asp:DataPager ID="ContactsDataPager" runat="server" PageSize="15">
<Fields>
<asp:NextPreviousPagerField ButtonType="Button"
ShowFirstPageButton="true"
ShowNextPageButton="false"
ShowPreviousPageButton="false" />
<asp:NumericPagerField ButtonCount="10" />
<asp:NextPreviousPagerField ButtonType="Button"
ShowLastPageButton="true"
ShowNextPageButton="false"
ShowPreviousPageButton="false" />
</Fields>
</asp:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr class="item" runat="server">
<td>
<asp:LinkButton ID="SelectButton" runat="server" CommandName="Select" Text="Select" />
</td>
<td>
<asp:Label ID="ContactIDLabel" runat="server" Text='<%# Eval("ContactID") %>' />
</td>
<td>
<asp:Label ID="FirstNameLabel" runat="server" Text='<%# Eval("FirstName") %>' />
</td>
<td>
<asp:Label ID="LastNameLabel" runat="server" Text='<%# Eval("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailLabel" runat="server" Text='<%# Eval("EmailAddress") %>' />
</td>
</tr>
</ItemTemplate>
<SelectedItemTemplate>
<tr class="selectedItem" runat="server">
<td> </td>
<td>
<asp:Label ID="ContactIDLabel" runat="server" Text='<%# Eval("ContactID") %>' />
</td>
<td>
<asp:Label ID="FirstNameLabel" runat="server" Text='<%# Eval("FirstName") %>' />
</td>
<td>
<asp:Label ID="LastNameLabel" runat="server" Text='<%# Eval("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailLabel" runat="server" Text='<%# Eval("EmailAddress") %>' />
</td>
</tr>
</SelectedItemTemplate>
</asp:ListView>
<br />
<br />
<asp:Button ID="DeleteButton"
Text="Delete Selected Contact"
OnClick="DeleteButton_Click"
runat="server" />
<br />
<asp:Label ID="Message"
ForeColor="Red"
runat="server"/>
<br/>
<!-- 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)" >
</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">
' <Snippet2>
Protected Sub DeleteButton_Click(ByVal sender As Object, ByVal e As EventArgs)
' Check if an item is selected to delete it.
If ContactsListView.SelectedIndex >= 0 Then
ContactsListView.DeleteItem(ContactsListView.SelectedIndex)
Else
Message.Text = "No contact was selected."
End If
End Sub
' </Snippet2>
Protected Sub ContactsListView_ItemDeleted(ByVal sender As Object, _
ByVal e As ListViewDeletedEventArgs)
' Check if an exception occurred to display an error message.
If Not (e.Exception Is Nothing) Then
Message.Text = "An exception occurred deleting the contact."
e.ExceptionHandled = True
Else
' Clear the selected index.
ContactsListView.SelectedIndex = -1
End If
End Sub
Protected Sub ContactsListView_PagePropertiesChanging(ByVal sender As Object, _
ByVal e As PagePropertiesChangingEventArgs)
' Clear the selected index.
ContactsListView.SelectedIndex = -1
End Sub
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Clear the message label.
Message.Text = ""
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>ListView DeleteItem Example</title>
<style type="text/css">
body
{
font-size: 10pt;
font-family: Trebuchet MS, Arial, Tahoma;
text-align:center;
}
.item { background-color: #E0FFFF }
.selectedItem { background-color: #B0E0E6 }
</style>
</head>
<body>
<form id="form1" runat="server">
<h3>ListView DeleteItem Example</h3>
<asp:ListView ID="ContactsListView"
DataSourceID="ContactsDataSource"
DataKeyNames="ContactID"
OnItemDeleted="ContactsListView_ItemDeleted"
OnPagePropertiesChanging="ContactsListView_PagePropertiesChanging"
runat="server" >
<LayoutTemplate>
<table cellpadding="2" width="640px" id="tblProducts" runat="server">
<tr runat="server">
<th runat="server"> </th>
<th runat="server">ID</th>
<th runat="server">Account Number</th>
<th runat="server">LastName</th>
<th runat="server">Preferred Vendor</th>
</tr>
<tr runat="server" id="itemPlaceholder" />
</table>
<asp:DataPager ID="ContactsDataPager" runat="server" PageSize="15">
<Fields>
<asp:NextPreviousPagerField ButtonType="Button"
ShowFirstPageButton="true"
ShowNextPageButton="false"
ShowPreviousPageButton="false" />
<asp:NumericPagerField ButtonCount="10" />
<asp:NextPreviousPagerField ButtonType="Button"
ShowLastPageButton="true"
ShowNextPageButton="false"
ShowPreviousPageButton="false" />
</Fields>
</asp:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr class="item" runat="server">
<td>
<asp:LinkButton ID="SelectButton" runat="server" CommandName="Select" Text="Select" />
</td>
<td>
<asp:Label ID="ContactIDLabel" runat="server" Text='<%# Eval("ContactID") %>' />
</td>
<td>
<asp:Label ID="FirstNameLabel" runat="server" Text='<%# Eval("FirstName") %>' />
</td>
<td>
<asp:Label ID="LastNameLabel" runat="server" Text='<%# Eval("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailLabel" runat="server" Text='<%# Eval("EmailAddress") %>' />
</td>
</tr>
</ItemTemplate>
<SelectedItemTemplate>
<tr class="selectedItem" runat="server">
<td> </td>
<td>
<asp:Label ID="ContactIDLabel" runat="server" Text='<%# Eval("ContactID") %>' />
</td>
<td>
<asp:Label ID="FirstNameLabel" runat="server" Text='<%# Eval("FirstName") %>' />
</td>
<td>
<asp:Label ID="LastNameLabel" runat="server" Text='<%# Eval("LastName") %>' />
</td>
<td>
<asp:Label ID="EmailLabel" runat="server" Text='<%# Eval("EmailAddress") %>' />
</td>
</tr>
</SelectedItemTemplate>
</asp:ListView>
<br />
<br />
<asp:Button ID="DeleteButton"
Text="Delete Selected Contact"
OnClick="DeleteButton_Click"
runat="server" />
<br />
<asp:Label ID="Message"
ForeColor="Red"
runat="server"/>
<br/>
<!-- 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)" >
</asp:SqlDataSource>
</form>
</body>
</html>
Hinweise
Verwenden Sie die DeleteItem -Methode, um den Datensatz am angegebenen Index programmgesteuert aus der Datenquelle zu löschen. Diese Methode wird in der Regel verwendet, um einen Datensatz außerhalb des ListView Steuerelements zu löschen, z. B. aus einem anderen Steuerelement auf der Seite. Diese Methode löst die ItemDeleted Ereignisse und ItemDeleting aus.
Gilt für:
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