GridView.RowCommand Event

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Occurs when a button is clicked in a GridView control.

public:
 event System::Web::UI::WebControls::GridViewCommandEventHandler ^ RowCommand;

public event System.Web.UI.WebControls.GridViewCommandEventHandler RowCommand;

member this.RowCommand : System.Web.UI.WebControls.GridViewCommandEventHandler

Public Custom Event RowCommand As GridViewCommandEventHandler

Event Type

GridViewCommandEventHandler

Examples

A Visual Studio Web site project with source code is available to accompany this topic: Download.

The following example demonstrates how to use the RowCommand event to add the name of a customer from a GridView control to a ListBox control when a row's Add button is clicked.


<%@ 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 ContactsGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
  {
    // If multiple buttons are used in a GridView control, 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.
      GridViewRow row = ContactsGridView.Rows[index];

      // Create a new ListItem object for the contact in the row.     
      ListItem item = new ListItem();
      item.Text = Server.HtmlDecode(row.Cells[2].Text) + " " +
        Server.HtmlDecode(row.Cells[3].Text);

      // If the contact is not already in the ListBox, add the ListItem 
      // object to the Items collection of the ListBox control. 
      if (!ContactsListBox.Items.Contains(item))
      {
        ContactsListBox.Items.Add(item);
      }
    }
  }    
</script>

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

      <h3>GridView RowCommand Example</h3>

      <table width="100%">
        <tr>
          <td style="width:50%">

            <asp:gridview id="ContactsGridView" 
              datasourceid="ContactsSource"
              allowpaging="true" 
              autogeneratecolumns="false"
              onrowcommand="ContactsGridView_RowCommand"
              runat="server">

              <columns>
                <asp:buttonfield buttontype="Link" 
                  commandname="Add" 
                  text="Add"/>
                <asp:boundfield datafield="ContactID" 
                  headertext="Contact ID"/>
                <asp:boundfield datafield="FirstName" 
                  headertext="First Name"/> 
                <asp:boundfield datafield="LastName" 
                  headertext="Last Name"/>
              </columns>

            </asp:gridview>

          </td>

          <td style="vertical-align:top; width:50%">

            Contacts: <br/>
            <asp:listbox id="ContactsListBox"
              runat="server" Height="200px" Width="200px"/>

          </td>
        </tr>
      </table>

      <!-- 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="ContactsSource"
        selectcommand="Select [ContactID], [FirstName], [LastName] From Person.Contact"
        connectionstring="<%$ ConnectionStrings:AdventureWorks_DataConnectionString%>" 
        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 ContactsGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)

    ' If multiple buttons are used in a GridView control, 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.
      Dim row As GridViewRow = ContactsGridView.Rows(index)
            
      ' Create a new ListItem object for the contact in the row.     
      Dim item As New ListItem()
      item.Text = Server.HtmlDecode(row.Cells(2).Text) & " " & _
        Server.HtmlDecode(row.Cells(3).Text)
            
      ' If the contact is not already in the ListBox, add the ListItem 
      ' object to the Items collection of the ListBox control. 
      If Not ContactsListBox.Items.Contains(item) Then
      
        ContactsListBox.Items.Add(item)
        
      End If
      
    End If
    
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>GridView RowCommand Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>GridView RowCommand Example</h3>

      <table width="100%">
        <tr>
          <td style="width:50%">

            <asp:gridview id="ContactsGridView" 
              datasourceid="ContactsSource"
              allowpaging="true" 
              autogeneratecolumns="false"
              onrowcommand="ContactsGridView_RowCommand"
              runat="server">

              <columns>
                <asp:buttonfield buttontype="Link" 
                  commandname="Add" 
                  text="Add"/>
                <asp:boundfield datafield="ContactID" 
                  headertext="Contact ID"/>
                <asp:boundfield datafield="FirstName" 
                  headertext="First Name"/> 
                <asp:boundfield datafield="LastName" 
                  headertext="Last Name"/>
              </columns>

            </asp:gridview>

          </td>

          <td style="vertical-align:top; width:50%">

            Contacts: <br/>
            <asp:listbox id="ContactsListBox"
              runat="server" Height="200px" Width="200px"/>

          </td>
        </tr>
      </table>

      <!-- 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="ContactsSource"
        selectcommand="Select [ContactID], [FirstName], [LastName] From Person.Contact"
        connectionstring="<%$ ConnectionStrings:AdventureWorks_DataConnectionString%>" 
        runat="server"/>

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

The following example demonstrates how to use the RowCommand event to update the price of a product when a row's button is clicked. This example has the paging functionality enabled for the GridView control and sets the CommandArgument property of the Button control to the appropriate row index.


<%@ 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 ProductsGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
  {
    // If multiple buttons are used in a GridView control, use the
    // CommandName property to determine which button was clicked.
    if(e.CommandName=="Increase")
    {
      // 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.      
      GridViewRow row = ProductsGridView.Rows[index];

      // Calculate the new price.
      Label listPriceTextBox = (Label)row.FindControl("PriceLabel");
      listPriceTextBox.Text = (Convert.ToDouble(listPriceTextBox.Text) * 1.05).ToString();     

      // Update the row.
      ProductsGridView.UpdateRow(index, false);
    }
  }
</script>

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

      <h3>GridView RowCommand Example</h3>

      <asp:GridView id="ProductsGridView" 
        DataSourceID="ProductsDataSource"
        DataKeyNames="ProductID"
        AllowPaging="True" 
        OnRowCommand="ProductsGridView_RowCommand"
        AutoGenerateColumns="False"
        runat="server">
        <Columns>
          <asp:BoundField DataField="Name" HeaderText="Product Name" />
          <asp:BoundField DataField="ProductNumber" HeaderText="Product Number" />          
          <asp:TemplateField HeaderText="Price">
            <ItemTemplate>
              <asp:Label ID="PriceLabel" runat="server" 
                Text='<%# Bind("ListPrice") %>'>
              </asp:Label>
            </ItemTemplate>
          </asp:TemplateField>
          <asp:TemplateField>
            <ItemTemplate>                
              <asp:Button runat="server" ID="IncreaseButton"
                Text="Increase Price 5%"
                CommandName="Increase"
                CommandArgument="<%# ((GridViewRow) Container).RowIndex %>" />
            </ItemTemplate>
          </asp:TemplateField>
        </Columns>
      </asp:GridView>

      <!-- 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="ProductsDataSource"
        SelectCommand="SELECT [ProductID], [Name], [ProductNumber], [ListPrice] 
          FROM Production.Product 
          WHERE ListPrice <> 0"
        UpdateCommand="UPDATE Production.Product SET [ListPrice] = @ListPrice 
          WHERE [ProductID] = @ProductID"
        ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
        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 ProductsGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)

    ' If multiple buttons are used in a GridView control, use the
    ' CommandName property to determine which button was clicked.
    If e.CommandName = "Increase" Then
    
      ' Convert the row index stored in the CommandArgument
      ' property to an Integer.
      Dim index = Convert.ToInt32(e.CommandArgument)
            
      ' Retrieve the row that contains the button clicked 
      ' by the user from the Rows collection.
      Dim row = ProductsGridView.Rows(index)
      
      ' Calculate the new price.
      Dim listPriceTextBox = CType(row.FindControl("PriceLabel"), Label)
      listPriceTextBox.Text = (Convert.ToDouble(listPriceTextBox.Text) * 1.05).ToString()

      ' Update the row.
      ProductsGridView.UpdateRow(index, False)
      
    End If
    
  End Sub
</script>

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

      <h3>GridView RowCommand Example</h3>

      <asp:GridView id="ProductsGridView" 
        DataSourceID="ProductsDataSource"
        DataKeyNames="ProductID"
        AllowPaging="True" 
        OnRowCommand="ProductsGridView_RowCommand"
        AutoGenerateColumns="False"
        runat="server">
        <Columns>
          <asp:BoundField DataField="Name" HeaderText="Product Name" />
          <asp:BoundField DataField="ProductNumber" HeaderText="Product Number" />          
          <asp:TemplateField HeaderText="Price">
            <ItemTemplate>
              <asp:Label ID="PriceLabel" runat="server" 
                Text='<%# Bind("ListPrice") %>'>
              </asp:Label>
            </ItemTemplate>
          </asp:TemplateField>
          <asp:TemplateField>
            <ItemTemplate>                
              <asp:Button runat="server" ID="IncreaseButton"
                Text="Increase Price 5%"
                CommandName="Increase"
                CommandArgument="<%# CType(Container, GridViewRow).RowIndex %>" />
            </ItemTemplate>
          </asp:TemplateField>
        </Columns>
      </asp:GridView>

      <!-- 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="ProductsDataSource"
        SelectCommand="SELECT [ProductID], [Name], [ProductNumber], [ListPrice] 
          FROM Production.Product 
          WHERE ListPrice <> 0"
        UpdateCommand="UPDATE Production.Product SET [ListPrice] = @ListPrice 
          WHERE [ProductID] = @ProductID"
        ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
        runat="server" />

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

Remarks

The RowCommand event is raised when a button is clicked in the GridView control. This enables you to provide an event-handling method that performs a custom routine whenever this event occurs.

Buttons within a GridView control can also invoke some of the built-in functionality of the control. To perform one of these operations, set the CommandName property of a button to one of the values in the following table.

`CommandName` value	Description
"Cancel"	Cancels an edit operation and returns the GridView control to read-only mode. Raises the RowCancelingEdit event.
"Delete"	Deletes the current record. Raises the RowDeleting and RowDeleted events.
"Edit"	Puts the current record in edit mode. Raises the RowEditing event.
"Page"	Performs a paging operation. Sets the `CommandArgument` property of the button to "First", "Last", "Next", "Prev", or a page number to specify the type of paging operation to perform. Raises the PageIndexChanging and PageIndexChanged events.
"Select"	Selects the current record. Raises the SelectedIndexChanging and SelectedIndexChanged events.
"Sort"	Sorts the GridView control. Raises the Sorting and Sorted events.
"Update"	Updates the current record in the data source. Raises the RowUpdating and RowUpdated events.

Although the RowCommand event is raised when a button listed in the previous table is clicked, it is recommended that you use the events listed in the table for the operation.

A GridViewCommandEventArgs object is passed to the event-handling method, which enables you to determine the command name and command argument of the button clicked.

Note

To determine the index of the row that raised the event, use the CommandArgument property of the event argument that is passed to the event. The ButtonField class automatically populates the CommandArgument property with the appropriate index value. For other command buttons, you must manually set the CommandArgument property of the command button. For example, you can set the CommandArgument to <%# Container.DataItemIndex %> when the GridView control has no paging enabled.

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

Applies to

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