CompareValidator.ControlPropertiesValid Method

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

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Checks the properties of the control for valid values.

protected:
 override bool ControlPropertiesValid();

protected override bool ControlPropertiesValid();

override this.ControlPropertiesValid : unit -> bool

Protected Overrides Function ControlPropertiesValid () As Boolean

Returns

Boolean

true if the control properties are valid; otherwise, false.

Exceptions

HttpException

ControlToValidate and ControlToCompare have the same ID.

-or-

The value of a target property cannot be converted to the expected Type.

Examples

The following code example demonstrates how to override the ControlPropertiesValid method in a custom server control so that it always returns the value of the visible property, as long as the ControlToCompare property of the CompareValidator control is on the page and contains validation properties.

Dôležité

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.

ASP.NET (C#)

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<%@ Page language="c#" %>
<!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>Custom CompareValidator - ControlPropertiesValid - C# Example</title>
    <script runat="server">
      void Page_Load(Object sender, EventArgs e)
      {
        // Run the Page Validate method in order to force
        // the CompareValidate to show it's error message.
        Page.Validate();
      }
    </script>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">
      <h3>Custom CompareValidator - ControlPropertiesValid - C# Example</h3>

      <asp:TextBox id="TextBox1" runat="server">123</asp:TextBox><br />

      <aspSample:CustomCompareValidatorControlPropertiesValid
        id="CompareValidator1"
        runat="server"
        Display="Dynamic"
        ErrorMessage="The value of TextBox1 must be '456'."
        ControlToValidate="TextBox1"
        ValueToCompare="456" /><br />

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

    </form>
  </body>
</html>

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB" %>
<%@ Page language="VB" %>
<!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>Custom CompareValidator - ControlPropertiesValid - VB.NET Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">
      <h3>Custom CompareValidator - ControlPropertiesValid - C# Example</h3>
            <asp:TextBox id="TextBox1" runat="server">123</asp:TextBox><br />
            <aspSample:CustomCompareValidatorControlPropertiesValid
             id="CompareValidator1" runat="server" Display="Dynamic"
             ErrorMessage="The value of TextBox1 must be '456'."
             ControlToValidate="TextBox1" ValueToCompare="456" /><br />
             <asp:Button id="Button1" runat="server" Text="Button" />
    </form>
  </body>
</html>

using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    public sealed class CustomCompareValidatorControlPropertiesValid : System.Web.UI.WebControls.CompareValidator
    {
        protected override bool ControlPropertiesValid()
        {
            // Determine whether the ControlToValidate is on the page and contains a validation properties. 
            base.CheckControlValidationProperty(this.ControlToValidate, "ControlToValidate");

            // If the control is visible, then control is valid and is ready for validation.
            System.Web.UI.Control control = this.FindControl(this.ControlToValidate);
            return control.Visible;
        }
    }
}

Imports System.Web
Imports System.Security.Permissions

Namespace Samples.AspNet.VB.Controls
    <AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
    Public NotInheritable Class CustomCompareValidatorControlPropertiesValid
        Inherits System.Web.UI.WebControls.CompareValidator

        Protected Overrides Function ControlPropertiesValid() As Boolean

            ' Determine whether the ControlToValidate is on the page and contains a validation properties. 
            MyBase.CheckControlValidationProperty(Me.ControlToValidate, "ControlToValidate")

            ' If the control is visible, then control is valid and ready for validation.
            Dim control As System.Web.UI.Control = Me.FindControl(Me.ControlToValidate)
            If control.Visible = True Then
                Return True
            Else
                Return False
            End If
        End Function
    End Class
End Namespace

Applies to

Produkt	Verzie
.NET Framework	1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

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