GridViewUpdateEventArgs.Keys Property


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

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

public IOrderedDictionary Keys { get; }

Property Value

Type: System.Collections.Specialized.IOrderedDictionary

A System.Collections.Specialized.IOrderedDictionary object containing field name/value pairs that represent the primary key of the row to update.

When the DataKeyNames property of a GridView control is set, use the Keys property (dictionary) to access the value of the primary key in the row to update.


To access the values of the non-key fields, use the NewValues or OldValues properties. The NewValues property contains the updated values, while the OldValues property contains the original values.

The Keys dictionary is automatically populated with the name/value pairs of the field or fields specified in the DataKeyNames property. If multiple fields form the primary key, a separate entry is added to the Keys dictionary for each key field.

To determine the name of a key field, use the DictionaryEntry.Key property of a System.Collections.DictionaryEntry object contained in the Keys dictionary. To determine the value of a key field, use the DictionaryEntry.Value property.

The following example demonstrates how to use the Keys property to access the values of the key fields in the row to update. The values are then written to a log file of updated records.

<%@ Page language="C#" %>
<%@ import namespace="System.IO" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "">

<script runat="server">

    void EmployeesGridView_RowUpdating(Object sender, GridViewUpdateEventArgs e)

        // Record the update operation in a log file.

        // Create the log text. 
        String logText = "";

        // Append the key field values to the log text.
        foreach (DictionaryEntry keyEntry in e.Keys)
            logText += keyEntry.Key + "=" + keyEntry.Value + ";";

        // Append the text to a log file.
        StreamWriter sw;
        sw = File.AppendText(Server.MapPath(null) + "\\updatelog.txt");


    void EmployeesGridView_RowUpdated(Object sender, GridViewUpdatedEventArgs e)

        if (e.Exception == null)
            // The update operation succeeded. Clear the message label.
            Message.Text = "";
            // The update operation failed. Display an error message.
            Message.Text = e.AffectedRows.ToString() + " rows updated. " + e.Exception.Message;
            e.ExceptionHandled = true;



<html xmlns="" >
<head id="Head1" runat="server">
    <title>GridViewUpdateEventArgs Keys Example</title>
        <form id="Form1" runat="server">

            <h3>GridViewUpdateEventArgs Keys Example</h3>

            <asp:label id="Message"


            <!-- The GridView control automatically sets the columns     -->
            <!-- specified in the datakeynames attribute as read-only.   -->
            <!-- No input controls are rendered for these columns in     -->
            <!-- edit mode.                                              -->
            <asp:gridview id="EmployeesGridView" 

            <!-- This example uses Microsoft SQL Server and connects -->
            <!-- to the Northwind sample database.                   -->
            <asp:sqldatasource id="EmployeesSqlDataSource"  
                selectcommand="SELECT [EmployeeID], [LastName], [FirstName], [HireDate] FROM [Employees]"
                updatecommand="UPDATE [Employees] SET [LastName] = @LastName, [FirstName] = @FirstName, [HireDate] = @HireDate WHERE [EmployeeID] = @EmployeeID" 
                ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>"
                runat="server" >


.NET Framework
Available since 2.0
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