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CompareValidator.ValueToCompare Property

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Gets or sets a constant value to compare with the value entered by the user in the input control being validated.

public:
 property System::String ^ ValueToCompare { System::String ^ get(); void set(System::String ^ value); };
[System.ComponentModel.Bindable(true)]
public string ValueToCompare { get; set; }
[System.Web.UI.Themeable(false)]
public string ValueToCompare { get; set; }
[<System.ComponentModel.Bindable(true)>]
member this.ValueToCompare : string with get, set
[<System.Web.UI.Themeable(false)>]
member this.ValueToCompare : string with get, set
Public Property ValueToCompare As String

Property Value

String

The constant value to compare with the value entered by the user in the input control being validated. The default value is Empty.

Attributes
BindableAttribute ThemeableAttribute

Examples

The following code example demonstrates how to use the ValueToCompare property to compare the value entered by the user in a TextBox control with a constant value.

Important

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

<%@ Page Language="C#" AutoEventWireup="True" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>CompareValidator ValueToCompare Example</title>
<script runat="server">
 
      void Button_Click(Object sender, EventArgs e) 
      {

         Random rand_number = new Random();

         Compare1.ValueToCompare = rand_number.Next(1, 10).ToString();
         Compare1.Validate();
 
         if (Page.IsValid) 
         {
            lblOutput.Text = "You guessed correctly!!";
         }
         else 
         {
            lblOutput.Text = "You guessed poorly";
         }

         lblOutput.Text += "<br /><br />" + "The number is: " + Compare1.ValueToCompare;

      }
 
   </script>
 
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>CompareValidator ValueToCompare Example</h3>

      <h5>Pick a number between 1 and 10:</h5>
      <asp:TextBox id="TextBox1" 
           runat="server"/>

      <br /><br />

      <asp:Button id="Button1"
           Text="Submit"
           OnClick="Button_Click"
           runat="server"/>

      <br /><br />
       
      <asp:CompareValidator id="Compare1" 
           ControlToValidate="TextBox1"
           ValueToCompare="0"  
           Type="Integer"
           EnableClientScript="False" 
           runat="server"/>
 
      <br />
       
      <asp:Label id="lblOutput" 
           Font-Names="verdana" 
           Font-Size="10pt" 
           runat="server"/>
 
   </form>
 
</body>
</html>

<%@ Page Language="VB" AutoEventWireup="True" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>CompareValidator ValueToCompare Example</title>
<script runat="server">
 
      Sub Button_Click(sender As Object, e As EventArgs) 

         Dim rand_number As New Random()

         Compare1.ValueToCompare = rand_number.Next(1, 10).ToString()
         Compare1.Validate()
 
         If Page.IsValid Then 
         
            lblOutput.Text = "You guessed correctly!!"
         
         Else 
         
            lblOutput.Text = "You guessed poorly"
         
         End If

         lblOutput.Text &= "<br /><br />" & "The number is: " & Compare1.ValueToCompare

      End Sub
 
   </script>
 
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>CompareValidator ValueToCompare Example</h3>

      <h5>Pick a number between 1 and 10:</h5>
      <asp:TextBox id="TextBox1" 
           runat="server"/>

      <br /><br />

      <asp:Button id="Button1"
           Text="Submit"
           OnClick="Button_Click"
           runat="server"/>

      <br /><br />
       
      <asp:CompareValidator id="Compare1" 
           ControlToValidate="TextBox1"
           ValueToCompare="0"  
           Type="Integer"
           EnableClientScript="False" 
           runat="server"/>
 
      <br />
       
      <asp:Label id="lblOutput" 
           Font-Names="verdana" 
           Font-Size="10pt" 
           runat="server"/>
 
   </form>
 
</body>
</html>

Remarks

Use the ValueToCompare property to specify a constant value to compare with the value entered by the user in the input control being validated. If the constant value specified by this property fails to convert to the data type specified by the BaseCompareValidator.Type property, an exception is thrown.

Note

Do not set both the ControlToCompare and the ValueToCompare property at the same time. You can either compare the value of an input control to another input control, or to a constant value. If both properties are set, the ControlToCompare property takes precedence.

This property cannot be set by themes or style sheet themes. For more information, see ThemeableAttribute and ASP.NET Themes and Skins.

Applies to

See also