CompareValidator Class

Determines validity by comparing a specific field in one control to a specific field in another control, using a specifiable comparison operator.

Namespace: System.Web.UI.MobileControls
Assembly: System.Web.Mobile (in

public class CompareValidator : BaseValidator
public class CompareValidator extends BaseValidator
public class CompareValidator extends BaseValidator

Use compare validators to ensure that the values of two text boxes provide the same values, such as confirming a new password.

This class behaves identically to the ASP.NET CompareValidator control.

By default, Command controls on a form raise any validator controls on the form to perform validation when the form is submitted to the server. To disable automatic validation, set the CausesValidation property on the Command controls to false.

Validation succeeds if the input control is empty. Use a RequiredFieldValidator control to require the user to enter data into the input control.

The following example code uses a CompareValidator control (CompareValidator1) to check whether the two text boxes have the same value and alerts the user if they are different.

<%@ Page Language="C#" 
    Inherits="System.Web.UI.MobileControls.MobilePage" %>
<%@ Register TagPrefix="mobile" 
    Assembly="System.Web.Mobile" %>

<html xmlns="" >
    <mobile:form id="form1" runat="server">
        <mobile:Label id="Label1" runat="server">Enter values
        <mobile:TextBox id="TextBox1" runat="server" Text="abc" />
        <mobile:TextBox id="TextBox2" runat="server" Text="xyz" />
        <mobile:Command id="Command1" runat="server" Text="OK" />
        <mobile:CompareValidator ID="CompareValidator1" Runat="server" 
            ErrorMessage="Values are different" Operator="Equal"
            ControlToValidate="TextBox2" />


  • 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.

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 Millennium Edition, 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, 1.1

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