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ListView.ItemUpdated Event

Definition

Occurs when an update operation is requested, after the ListView control updates the item.

public:
 event EventHandler<System::Web::UI::WebControls::ListViewUpdatedEventArgs ^> ^ ItemUpdated;
public event EventHandler<System.Web.UI.WebControls.ListViewUpdatedEventArgs> ItemUpdated;
member this.ItemUpdated : EventHandler<System.Web.UI.WebControls.ListViewUpdatedEventArgs> 
Public Custom Event ItemUpdated As EventHandler(Of ListViewUpdatedEventArgs) 

Event Type

Examples

The following example shows how to add an event handler for the ItemUpdated event.

Important

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

<%@ 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 Page_Load()
    {
        Message.Text = String.Empty;
    }
        
    //<Snippet2>
    void ContactsListView_ItemUpdated(Object sender, ListViewUpdatedEventArgs e)
    {
        if (e.Exception != null)
        {
            if (e.AffectedRows == 0)
            {
                e.KeepInEditMode = true;
                Message.Text = "An exception occurred updating the contact. " +
                                    "Please verify your values and try again.";
            }
            else
                Message.Text = "An exception occurred updating the contact. " +
                                    "Please verify the values in the recently updated item.";

            e.ExceptionHandled = true;
        }
    }
   //</Snippet2>
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>ListView.ItemUpdated Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>ListView.ItemUpdated Example</h3>
            
      <asp:Label ID="Message"
        ForeColor="Red"          
        runat="server"/>
      <br/>

      <asp:ListView ID="ContactsListView" 
        DataSourceID="ContactsDataSource" 
        DataKeyNames="ContactID"
        OnItemUpdated="ContactsListView_ItemUpdated"  
        runat="server">
        <LayoutTemplate>
          <table cellpadding="2" border="1" runat="server" id="tblContacts" width="640px">
            <tr runat="server" id="itemPlaceholder" />
          </table>
          <asp:DataPager runat="server" ID="PeopleDataPager" PageSize="12">
             <Fields>
               <asp:NextPreviousPagerField 
                ShowFirstPageButton="True" ShowLastPageButton="True"
                    FirstPageText="|&lt;&lt; " LastPageText=" &gt;&gt;|"
                    NextPageText=" &gt; " PreviousPageText=" &lt; " />
             </Fields>
           </asp:DataPager>
         </LayoutTemplate>
         <ItemTemplate>
            <tr runat="server">
              <td valign="top">
                <asp:Label ID="FirstNameLabel" runat="server" Text='<%#Eval("FirstName") %>' />
                <asp:Label ID="LastNameLabel" runat="server" Text='<%#Eval("LastName") %>' />
              </td>
              <td>
                <asp:Label ID="EmailLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
              </td>
              <td>
                <asp:LinkButton ID="EditButton" runat="server" CommandName="Edit" Text="Edit" />
              </td>
            </tr>
          </ItemTemplate>
          <EditItemTemplate>
            <tr style="background-color:#ADD8E6">
              <td valign="top">
                <asp:Label runat="server" ID="FirstNameLabel" 
                  AssociatedControlID="FirstNameTextBox" Text="First Name"/>
                <asp:TextBox ID="FirstNameTextBox" runat="server"
                  Text='<%# Bind("FirstName") %>' MaxLength="50" Width="200px" /><br />
                <asp:Label runat="server" ID="LastNameLabel" 
                  AssociatedControlID="LastNameTextBox" Text="Last Name" />
                <asp:TextBox ID="LastNameTextBox" runat="server" 
                  Text='<%# Bind("LastName") %>' MaxLength="50" Width="200px" /><br />
                <asp:Label runat="server" ID="EmailLabel" 
                  AssociatedControlID="EmailTextBox" Text="Email" />
                <asp:TextBox ID="EmailTextBox" runat="server" 
                  Text='<%# Bind("EmailAddress") %>' MaxLength="50" Width="200px" />
              </td>
              <td colspan="2" valign="top">
                <asp:LinkButton ID="UpdateButton" runat="server" CommandName="Update" Text="Update" />
                <asp:LinkButton ID="CancelButton" runat="server" CommandName="Cancel" Text="Cancel" />
              </td>
            </tr>
          </EditItemTemplate>
      </asp:ListView>

      <!-- 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"
        UpdateCommand="UPDATE Person.Contact
          Set [FirstName] = @FirstName, [LastName] = @LastName, [EmailAddress] = @EmailAddress 
          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">

    Sub Page_Load()
        Message.Text = String.Empty
    End Sub

    '<Snippet2>
    Sub ContactsListView_ItemUpdated(sender As Object, e As ListViewUpdatedEventArgs)
        If e.Exception IsNot Nothing Then
            If e.AffectedRows = 0 Then
                e.KeepInEditMode = True
                Message.Text = "An exception occurred updating the contact. " & _
                                    "Please verify your values and try again."
            Else
                Message.Text = "An exception occurred updating the contact. " & _
                                    "Please verify the values in the recently updated item."
            End If

            e.ExceptionHandled = True
        End If
    End Sub
   '</Snippet2>
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>ListView.ItemUpdated Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>ListView.ItemUpdated Example</h3>
            
      <asp:Label ID="Message"
        ForeColor="Red"          
        runat="server"/>
      <br/>

      <asp:ListView ID="ContactsListView" 
        DataSourceID="ContactsDataSource" 
        DataKeyNames="ContactID"
        OnItemUpdated="ContactsListView_ItemUpdated"  
        runat="server">
        <LayoutTemplate>
          <table cellpadding="2" border="1" runat="server" id="tblContacts" width="640px">
            <tr runat="server" id="itemPlaceholder" />
          </table>
          <asp:DataPager runat="server" ID="PeopleDataPager" PageSize="12">
             <Fields>
               <asp:NextPreviousPagerField 
                ShowFirstPageButton="True" ShowLastPageButton="True"
                    FirstPageText="|&lt;&lt; " LastPageText=" &gt;&gt;|"
                    NextPageText=" &gt; " PreviousPageText=" &lt; " />
             </Fields>
           </asp:DataPager>
         </LayoutTemplate>
         <ItemTemplate>
            <tr>
              <td valign="top">
                <asp:Label ID="FirstNameLabel" runat="server" Text='<%#Eval("FirstName") %>' />
                <asp:Label ID="LastNameLabel" runat="server" Text='<%#Eval("LastName") %>' />
              </td>
              <td>
                <asp:Label ID="EmailLabel" runat="server" Text='<%#Eval("EmailAddress") %>' />
              </td>
              <td>
                <asp:LinkButton ID="EditButton" runat="server" CommandName="Edit" Text="Edit" />
              </td>
            </tr>
          </ItemTemplate>
          <EditItemTemplate>
            <tr style="background-color:#ADD8E6">
              <td valign="top">
                <asp:Label runat="server" ID="FirstNameLabel" 
                  AssociatedControlID="FirstNameTextBox" Text="First Name"/>
                <asp:TextBox ID="FirstNameTextBox" runat="server"
                  Text='<%# Bind("FirstName") %>' MaxLength="50" Width="200px" /><br />
                <asp:Label runat="server" ID="LastNameLabel" 
                  AssociatedControlID="LastNameTextBox" Text="Last Name" />
                <asp:TextBox ID="LastNameTextBox" runat="server" 
                  Text='<%# Bind("LastName") %>' MaxLength="50" Width="200px" /><br />
                <asp:Label runat="server" ID="EmailLabel" 
                  AssociatedControlID="EmailTextBox" Text="Email" />
                <asp:TextBox ID="EmailTextBox" runat="server" 
                  Text='<%# Bind("EmailAddress") %>' MaxLength="50" Width="200px" />
              </td>
              <td colspan="2" valign="top">
                <asp:LinkButton ID="UpdateButton" runat="server" CommandName="Update" Text="Update" />
                <asp:LinkButton ID="CancelButton" runat="server" CommandName="Cancel" Text="Cancel" />
              </td>
            </tr>
          </EditItemTemplate>
      </asp:ListView>

      <!-- 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"
        UpdateCommand="UPDATE Person.Contact
          Set [FirstName] = @FirstName, [LastName] = @LastName, [EmailAddress] = @EmailAddress 
          WHERE [ContactID] = @ContactID">
      </asp:SqlDataSource>
      
    </form>
  </body>
</html>

Remarks

The ItemUpdated event is raised when an item's Update button is clicked or the UpdateItem method is called, after the ListView control updates the item. (An Update button is a button control whose CommandName property is set to "Update".) This enables you to perform a custom routine whenever this event occurs, such as checking the results of the update operation.

A ListViewUpdatedEventArgs object is passed to the event handler, which enables you to determine the number of rows affected. It also lets you determine what exceptions might have occurred. You can indicate whether the exception was handled in the event handler by setting the ExceptionHandled property of the ListViewUpdatedEventArgs object.

For more information about how to handle events, see Handling and Raising Events.

Applies to

See also