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GridViewUpdateEventArgs Class

Definition

Provides data for the RowUpdating event.

public ref class GridViewUpdateEventArgs : System::ComponentModel::CancelEventArgs
public class GridViewUpdateEventArgs : System.ComponentModel.CancelEventArgs
type GridViewUpdateEventArgs = class
    inherit CancelEventArgs
Public Class GridViewUpdateEventArgs
Inherits CancelEventArgs
Inheritance
GridViewUpdateEventArgs

Examples

The following example demonstrates how to use the GridViewUpdateEventArgs object passed to the event-handling method to HTML-encode all values supplied by the user before updating 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">

  void CustomersGridView_RowUpdating(Object sender, GridViewUpdateEventArgs e)
  {
     
    // Iterate through the NewValues collection and HTML encode all 
    // user-provided values before updating the data source.
    foreach (DictionaryEntry entry in e.NewValues)
    {
    
      e.NewValues[entry.Key] = Server.HtmlEncode(entry.Value.ToString());
    
    }
        
  }
       
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowUpdating Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowUpdating Example</h3>
            
      <!-- The GridView control automatically sets the columns     -->
      <!-- specified in the datakeynames property as read-only.    -->
      <!-- No input controls are rendered for these columns in     -->
      <!-- edit mode.                                              -->
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogenerateeditbutton="true"
        allowpaging="true" 
        datakeynames="CustomerID"
        onrowupdating="CustomersGridView_RowUpdating"  
        runat="server">
      </asp:gridview>
            
      <!-- 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="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </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 CustomersGridView_RowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
    
    ' Use the CopyTo method to copy the DictionaryEntry objects in the 
    ' NewValues collection to an array.
    Dim records(e.NewValues.Count - 1) As DictionaryEntry
    e.NewValues.CopyTo(records, 0)
    
    ' Iterate through the array and HTML encode all user-provided values 
    ' before updating the data source.
    Dim entry As DictionaryEntry
    For Each entry In records
            
      e.NewValues(entry.Key) = Server.HtmlEncode(entry.Value.ToString())
      
    Next
        
  End Sub
       
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowUpdating Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowUpdating Example</h3>
            
      <!-- The GridView control automatically sets the columns     -->
      <!-- specified in the datakeynames property as read-only.    -->
      <!-- No input controls are rendered for these columns in     -->
      <!-- edit mode.                                              -->
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogenerateeditbutton="true"
        allowpaging="true" 
        datakeynames="CustomerID"
        onrowupdating="CustomersGridView_RowUpdating"  
        runat="server">
      </asp:gridview>
            
      <!-- 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="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

Remarks

The GridView control raises the RowUpdating event when a row's Update button is clicked, but before the GridView control updates the row. This allows you to provide an event-handling method that performs a custom routine, such as canceling the update operation, whenever this event occurs.

A GridViewUpdateEventArgs object is passed to the event-handling method, which allows you to determine the index of the current row and to indicate that the update operation should be canceled. To cancel the update operation, set the Cancel property of the GridViewUpdateEventArgs object to true. You can also manipulate the Keys, OldValues, and NewValues collections, if necessary, before the values are passed to the data source. A common way to use these collections is to HTML-encode the values supplied by the user before they are stored in the data source. This helps to prevent script injection attacks.

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

For a list of initial property values for an instance of GridViewUpdateEventArgs, see the GridViewSelectEventArgs constructor.

Constructors

GridViewUpdateEventArgs(Int32)

Initializes a new instance of the GridViewUpdateEventArgs class.

Properties

Cancel

Gets or sets a value indicating whether the event should be canceled.

(Inherited from CancelEventArgs)
Keys

Gets a dictionary of field name/value pairs that represent the primary key of the row to update.

NewValues

Gets a dictionary containing the revised values of the non-key field name/value pairs in the row to update.

OldValues

Gets a dictionary containing the original field name/value pairs in the row to update.

RowIndex

Gets the index of the row being updated.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also