FormViewCommandEventArgs Class

Note: This class is new in the .NET Framework version 2.0.

Provides data for the ItemCommand event.

Namespace: System.Web.UI.WebControls
Assembly: System.Web (in system.web.dll)

'Declaration
Public Class FormViewCommandEventArgs
	Inherits CommandEventArgs
'Usage
Dim instance As FormViewCommandEventArgs

public class FormViewCommandEventArgs extends CommandEventArgs
public class FormViewCommandEventArgs extends CommandEventArgs

The ItemCommand event is raised when a button within the FormView control is clicked. This allows you to provide an event-handling method that performs a custom routine whenever this event occurs.

Buttons within a FormView 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 or insert operation and returns the FormView control to the mode specified by the DefaultMode property. Raises the ModeChanged and ModeChanging events.

"Delete"

Deletes the current record. Raises the ItemDeleted and ItemDeleting events.

"Edit"

Puts the FormView control in edit mode. Raises the ModeChanged and ModeChanging events.

"Insert"

Inserts the current record in the data source. Raises the ItemInserted and ItemInserting events.

"New"

Puts the FormView control in insert mode. Raises the ModeChanged and ModeChanging events.

"Page"

Performs a paging operation. Set 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 PageIndexChanged and PageIndexChanging events.

"Update"

Updates the current record in the data source. Raises the ItemUpdated and ItemUpdating events.

Although the ItemCommand 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 FormViewCommandEventArgs object is passed to the event-handling method, which allows you to determine the command name and command argument of the button clicked. To determine the command name and command argument, use the CommandName and CommandArgument properties, respectively. You can also access the button control that raised the event by using the CommandSource property.

For more information about handling events, see Consuming Events.

For a list of initial property values for an instance of the FormViewCommandEventArgs class, see the FormViewCommandEventArgs constructor.

The following example demonstrates how to use the FormViewCommandEventArgs object passed to the event-handling method for the ItemCommand event to determine which button within a FormView control was clicked by the user.


<%@ Page language="VB" %>

<script runat="server">

  Sub ProductFormView_ItemCommand(ByVal sender As Object, ByVal e As FormViewCommandEventArgs)

    ' The ItemCommand event is raised when any button within
    ' the FormView control is clicked. Use the CommandName property 
    ' to determine which button was clicked. 
    If e.CommandName = "Add" Then

      ' Add the product to the ListBox control. 
      
      ' Use the Row property to retrieve the data row.
      Dim row As FormViewRow = ProductFormView.Row
      
      ' Retrieve the ProductNameLabel control from
      ' the data row.
      Dim productNameLabel As Label = CType(row.FindControl("ProductNameLabel"), Label)

      ' Retrieve the QuantityTextBox control from
      ' the data row.
      Dim quantityTextBox As TextBox = CType(row.FindControl("QuantityTextBox"), TextBox)

      If productNameLabel IsNot Nothing And quantityTextBox IsNot Nothing Then
          
        ' Get the product name from the ProductNameLabel control.
        Dim name As String = productNameLabel.Text
        
        ' Get the quantity from the QuantityTextBox control.
        Dim quantity As String = quantityTextBox.Text

        ' Create the text to display in the ListBox control.
        Dim description As String = name & " - " & quantity & " Qty"

        ' Create a ListItem object using the description and
        ' product name.
        Dim item As new ListItem(description, name)

        ' Add the ListItem object to the ListBox.
        ProductListBox.Items.Add(item)

        ' Use the CommandSource property to retrieve
        ' the Add button. Disable the button after
        ' the user adds the currently displayed employee
        ' name to the ListBox control.
        Dim addButton As Button = CType(e.CommandSource, Button)
        addButton.Enabled = False
        
      End If

    End If

  End Sub

  Sub ProductFormView_DataBound(ByVal sender As Object, ByVal e As EventArgs)
    
    ' To prevent the user from adding duplicate items, 
    ' disable the Add button if the item being bound to the 
    ' FormView control is already in the ListBox control.
    
    ' Use the Row property to retrieve the data row.
    Dim row As FormViewRow = ProductFormView.Row

    ' Retrieve the Add button from the data row.
    Dim addButton As Button = CType(row.FindControl("AddButton"), Button)

    ' Retrieve the ProductNameLabel control from
    ' data row.
    Dim productNameLabel As Label = CType(row.FindControl("ProductNameLabel"), Label)

    If addButton IsNot Nothing And productNameLabel IsNot Nothing Then
    
      ' Get the product name from the ProductNameLabel 
      ' control.
      Dim name As String = productNameLabel.Text

      ' Use the FindByValue method to determine whether
      ' the ListBox control already contains an entry for
      ' the item.
      Dim item As ListItem = ProductListBox.Items.FindByValue(name)

      ' Disable the Add button if the ListBox control
      ' already contains the item.
      If item IsNot Nothing Then
      
        addButton.Enabled = False
      
      Else
      
        addButton.Enabled = True
        
      End If
      
    End If

  End Sub
    
</script>

<html>
  <body>
    <form runat="server">
        
      <h3>FormViewCommandEventArgs Example</h3>
                       
      <asp:formview id="ProductFormView"
        datasourceid="ProductSource"
        allowpaging="true"
        datakeynames="ProductID"
        onitemcommand="ProductFormView_ItemCommand"
        ondatabound="ProductFormView_DataBound"  
        runat="server">
        
        <itemtemplate>
        
          <table>
            <tr>
              <td width="400px">
                <b>Description:</b>
                <asp:label id="ProductNameLabel"
                  text='<%# Eval("ProductName") %>'
                  runat='server'/>
                <br/>      
                <b>Price:</b>
                <asp:label id="PriceLabel"
                  text='<%# Eval("UnitPrice", "{0:c}") %>'
                  runat='server'/>
                <br/>  
                <asp:textbox id="QuantityTextBox"
                  width="50px"
                  maxlength="3" 
                  runat="server"/> Qty                   
              </td>
            </tr>
            <tr>
              <td>
                <asp:requiredfieldvalidator ID="QuantityRequiredValidator"
                  controltovalidate="QuantityTextBox"
                  text="Please enter a quantity."
                  display="Static"
                  runat="server"/>
                <br/>
                <asp:CompareValidator id="QuantityCompareValidator"
                  controltovalidate="QuantityTextBox"
                  text="Please enter an integer value."
                  display="Static"
                  type="Integer"
                  operator="DataTypeCheck"  
                  runat="server"/>    
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:button id="AddButton"
                  text="Add"
                  commandname="Add"
                  runat="server"/>
              </td>
            </tr>
          </table>
        
        </itemtemplate>
                  
      </asp:formview>
      
      <br/><br/><hr/>
      
      Items:<br/>
      <asp:listbox id="ProductListBox"
        runat="server"/>
          
      <!-- 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="ProductSource"
        selectcommand="Select [ProductID], [ProductName], [UnitPrice] From [Products]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>


  • AspNetHostingPermission  For operating in a hosted environment. Demand value: LinkDemand; Permission value: Minimal.
  • AspNetHostingPermission  For operating in a hosted environment. Demand value: InheritanceDemand; Permission value: Minimal.

System.Object
   System.EventArgs
     System.Web.UI.WebControls.CommandEventArgs
      System.Web.UI.WebControls.FormViewCommandEventArgs

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 98, Windows 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0

Community Additions

ADD
Show: