GridViewCommandEventArgs.CommandSource Property

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

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Gets the source of the command.

public:
 property System::Object ^ CommandSource { System::Object ^ get(); };

public object CommandSource { get; }

member this.CommandSource : obj

Public ReadOnly Property CommandSource As Object

Property Value

Object

A instance of the Object class that represents the source of the command.

Examples

The following example demonstrates how to use the CommandSource property to access the GridView control that contains the button clicked by the user.


<%@ 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 CustomersGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
  {
    // If multiple ButtonField columns are used, use the
    // CommandName property to determine which button was clicked.
    if(e.CommandName=="Add")
    {
      // Convert the row index stored in the CommandArgument
      // property to an Integer.
      int index = Convert.ToInt32(e.CommandArgument);

      // Retrieve the row that contains the button clicked
      // by the user from the Rows collection. Use the
      // CommandSource property to access the GridView control.
      GridView customersGridView = (GridView)e.CommandSource;
      GridViewRow row = customersGridView.Rows[index];

      // Create a new ListItem object for the customer in the row.
      ListItem item = new ListItem();
      item.Text = Server.HtmlDecode(row.Cells[1].Text) + " " + Server.HtmlDecode(row.Cells[2].Text);

      // If the author is not already in the ListBox, add the ListItem
      // object to the Items collection of a ListBox control.
      if(!CustomersListBox.Items.Contains(item))
      {
        CustomersListBox.Items.Add(item);
      }
    }
  }

  void CustomersGridView_RowCreated(Object sender, GridViewRowEventArgs e)
  {

    // The GridViewCommandEventArgs class does not contain a
    // property that indicates which row's command button was
    // clicked. To identify which row was clicked, use the button's
    // CommandArgument property by setting it to the row's index.
    if(e.Row.RowType == DataControlRowType.DataRow)
    {
      // Retrieve the LinkButton control from the first column.
      LinkButton addButton = (LinkButton)e.Row.Cells[0].Controls[0];

      // Set the LinkButton's CommandArgument property with the
      // row's index.
      addButton.CommandArgument = e.Row.RowIndex.ToString();
    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewCommandEventArgs Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>GridViewCommandEventArgs Example</h3>

      <table width="100%">
        <tr>
          <td style="width:50%">
            <asp:gridview id="CustomersGridView" 
              datasourceid="CustomersSource" 
              autogeneratecolumns="false"
              onrowcommand="CustomersGridView_RowCommand"
              onrowcreated="CustomersGridView_RowCreated"  
              runat="server">
                
              <columns>
                
                <asp:buttonfield buttontype="Link" commandname="Add" text="Add"/>
                <asp:boundfield datafield="CompanyName" 
                  headertext="Company Name"/>
                <asp:boundfield datafield="City" 
                  headertext="City"/>
                
              </columns>
                
            </asp:gridview>
          </td>

          <td style="vertical-align:top; width:50%">
             Customers: <br/>
             <asp:listbox id="CustomersListBox"
               runat="server"/>
          </td>
        </tr>
      </table>

      <!-- 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="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [City] From [Customers]"
        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 CustomersGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)
  
    ' If multiple ButtonField columns are used, use the
    ' CommandName property to determine which button was clicked.
    If e.CommandName = "Add" Then
    
      ' Convert the row index stored in the CommandArgument
      ' property to an Integer.
      Dim index As Integer = Convert.ToInt32(e.CommandArgument)

      ' Retrieve the row that contains the button clicked
      ' by the user from the Rows collection. Use the
      ' CommandSource property to access the GridView control.
      Dim customersGridView As GridView = CType(e.CommandSource, GridView)
      Dim row As GridViewRow = customersGridView.Rows(index)

      ' Create a new ListItem object for the customer in the row.
      Dim item As New ListItem()
      item.Text = Server.HtmlDecode(row.Cells(1).Text) + " " + Server.HtmlDecode(row.Cells(2).Text)

      ' If the author is not already in the ListBox, add the ListItem
      ' object to the Items collection of a ListBox control.
      If Not CustomersListBox.Items.Contains(item) Then
      
        CustomersListBox.Items.Add(item)
        
      End If
    End If
        
  End Sub

  Sub CustomersGridView_RowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs)

    ' The GridViewCommandEventArgs class does not contain a
    ' property that indicates which row's command button was
    ' clicked. To identify which row was clicked, use the button's
    ' CommandArgument property by setting it to the row's index.
    If e.Row.RowType = DataControlRowType.DataRow Then

      ' Retrieve the LinkButton control from the first column.
      Dim addButton As LinkButton = CType(e.Row.Cells(0).Controls(0), LinkButton)

      ' Set the LinkButton's CommandArgument property with the
      ' row's index.
      addButton.CommandArgument = e.Row.RowIndex.ToString()
      
    End If

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewCommandEventArgs Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>GridViewCommandEventArgs Example</h3>

      <table width="100%">
        <tr>
          <td style="width:50%">
            <asp:gridview id="CustomersGridView" 
              datasourceid="CustomersSource" 
              autogeneratecolumns="false"
              onrowcommand="CustomersGridView_RowCommand"
              onrowcreated="CustomersGridView_RowCreated"  
              runat="server">
                
              <columns>
                
                <asp:buttonfield buttontype="Link" commandname="Add" text="Add"/>
                <asp:boundfield datafield="CompanyName" 
                  headertext="Company Name"/>
                <asp:boundfield datafield="City" 
                  headertext="City"/>
                
              </columns>
                
            </asp:gridview>
          </td>

          <td style="vertical-align:top; width:50%">
             Customers: <br/>
             <asp:listbox id="CustomersListBox"
               runat="server"/>
          </td>
        </tr>
      </table>

      <!-- 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="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [City] From [Customers]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>

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

Remarks

Use the CommandSource property to access the properties of the object that represents the source of the command. In the case of a GridViewCommandEventArgs object, the source of the command is the GridView control that contains the button clicked by the user.

Applies to

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