ListView.UpdateItem(Int32, Boolean) Method

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.Extensions.dll

Important

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Updates the record at the specified index in the data source.

public:
 virtual void UpdateItem(int itemIndex, bool causesValidation);

public virtual void UpdateItem (int itemIndex, bool causesValidation);

abstract member UpdateItem : int * bool -> unit
override this.UpdateItem : int * bool -> unit

Public Overridable Sub UpdateItem (itemIndex As Integer, causesValidation As Boolean)

Parameters

itemIndex: Int32

The index of the item to update.

causesValidation: Boolean

true to perform page validation when this method is called; otherwise, false.

Exceptions

InvalidOperationException

itemIndex is less than 0.

-or-

The DataSourceView object that is associated with the ListView control is null.

Examples

The following example shows how to use the UpdateItem method to programmatically update a ListView item in the data source.

<%@ 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 PreferredCheckBox_CheckedChanged(object sender, EventArgs e)
  {
    // Gets the CheckBox object that fired the event.
    CheckBox chkBox = (CheckBox) sender;

    // Gets the item that contains the CheckBox object. 
    ListViewDataItem item = (ListViewDataItem) chkBox.Parent.Parent;
    
    // Update the database with the changes.
    VendorsListView.UpdateItem(item.DisplayIndex, false);
  }
  // </Snippet2>
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>ListView UpdateItem Example</title>
  </head>
  <body>
    <form id="form1" runat="server">
        
      <h3>ListView UpdateItem Example</h3>
      
      <asp:ListView ID="VendorsListView" 
        DataSourceID="VendorsDataSource"
        DataKeyNames="VendorID"
        runat="server">
        <LayoutTemplate>
          Select your preferred vendors:
          <ul runat="server" id="lstVendors" style="text-align:left">
            <li runat="server" id="itemPlaceholder" />
          </ul>
          <asp:DataPager ID="VendorsDataPager" runat="server" PageSize="15">
            <Fields>
              <asp:NumericPagerField ButtonCount="10" />
            </Fields>
          </asp:DataPager>
        </LayoutTemplate>
        <ItemTemplate>
          <li runat="server">
            <asp:CheckBox runat="server" ID="PreferredCheckBox" AutoPostBack="True" 
              Checked='<%# Bind("PreferredVendorStatus") %>' 				        
              OnCheckedChanged="PreferredCheckBox_CheckedChanged" />
            <asp:Label runat="server" ID="NameLabel" text='<%# Eval("Name") %>' /><br/>
          </li>
        </ItemTemplate>
      </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="VendorsDataSource" runat="server" 
        ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
        SelectCommand="SELECT VendorID, Name, PreferredVendorStatus
          FROM Purchasing.Vendor WHERE (ActiveFlag = 1)" 
        UpdateCommand="UPDATE Purchasing.Vendor 
          SET PreferredVendorStatus = @PreferredVendorStatus 
          WHERE (VendorID = @VendorID)" >
      </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 PreferredCheckBox_CheckedChanged(ByVal sender As Object, ByVal e As EventArgs) 
  
    ' Gets the CheckBox object that fired the event.
    Dim chkBox As CheckBox = CType(sender, CheckBox)
    
    ' Gets the item that contains the CheckBox object. 
    Dim item As ListViewDataItem = CType(chkBox.Parent.Parent, ListViewDataItem)
    
    ' Update the database with the changes.
    VendorsListView.UpdateItem(item.DisplayIndex, False)    

  End Sub
  ' </Snippet2>
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>ListView UpdateItem Example</title>
  </head>
  <body>
    <form id="form1" runat="server">
        
      <h3>ListView UpdateItem Example</h3>
      
      <asp:ListView ID="VendorsListView" 
        DataSourceID="VendorsDataSource"
        DataKeyNames="VendorID"
        runat="server">
        <LayoutTemplate>
          Select your preferred vendors:
          <ul runat="server" id="lstVendors" style="text-align:left">
            <li runat="server" id="itemPlaceholder" />
          </ul>
          <asp:DataPager ID="VendorsDataPager" runat="server" PageSize="15">
            <Fields>
              <asp:NumericPagerField ButtonCount="10" />
            </Fields>
          </asp:DataPager>
        </LayoutTemplate>
        <ItemTemplate>
          <li runat="server">
            <asp:CheckBox runat="server" ID="PreferredCheckBox" AutoPostBack="True" 
              Checked='<%# Bind("PreferredVendorStatus") %>' 				        
              OnCheckedChanged="PreferredCheckBox_CheckedChanged" />
            <asp:Label runat="server" ID="NameLabel" text='<%# Eval("Name") %>' /><br/>
          </li>
        </ItemTemplate>
      </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="VendorsDataSource" runat="server" 
        ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
        SelectCommand="SELECT VendorID, Name, PreferredVendorStatus
          FROM Purchasing.Vendor WHERE (ActiveFlag = 1)" 
        UpdateCommand="UPDATE Purchasing.Vendor 
          SET PreferredVendorStatus = @PreferredVendorStatus 
          WHERE (VendorID = @VendorID)" >
      </asp:SqlDataSource>

    </form>
  </body>
</html>

Remarks

Use the UpdateItem method to programmatically update the record at the specified index in the data source. You typically use this method when you want to update a record from outside the ListView control, such as from a different control on the page.

Note

This method can be called only for an item that contains a two-way data-bound input control. For more information about two-way binding expressions, see Binding to Databases.

To specify whether page validation is performed before the update operation, use the causesValidation parameter.

This method raises the ItemUpdated and ItemUpdating events.

Applies to

Megosztás a következőn keresztül: