RangeValidator.EvaluateIsValid Method
.NET Framework 3.0
This method supports the .NET Framework infrastructure and is not intended to be used directly from your code.
Determines whether the content in the input control is valid.
Namespace: System.Web.UI.WebControlsAssembly: System.Web (in system.web.dll)
The following code example demonstrates how to override the EvaluateIsValid method in a custom server control so that it always validates that the value exists and is within the maximum and minimum values specified for the RangeValidator.
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.JSL.Controls" Assembly="Samples.AspNet.JSL" %>
<%@ Page Language="VJ#" 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>Custom RangeValidator - EvaluateIsValid - VJ# Example</title>
<script runat="server">
void ButtonClick(Object sender, EventArgs e)
{
if (get_Page().get_IsValid()) {
Label1.set_Text("Page is valid.");
}
else {
Label1.set_Text("Page is not valid!!");
}
} //ButtonClick
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom RangeValidator - EvaluateIsValid - VJ# Example</h3>
Enter a number from 1 to 10:<br />
<asp:TextBox id="TextBox1" Runat="server" />
<aspSample:CustomRangeValidatorEvaluateIsValid
id="RangeValidator1"
runat="server"
ControlToValidate="TextBox1"
MinimumValue="1"
MaximumValue="10"
Type="Integer"
EnableClientScript="false"
Text="The value must be from 1 to 10!" />
<br />
<br />
<asp:Button id="Button1" Text="Submit" OnClick="ButtonClick" runat="server" /><br />
<br />
<asp:Label id="Label1" runat="server" />
</form>
</body>
</html>
...
package Samples.AspNet.JSL.Controls;
public class CustomRangeValidatorEvaluateIsValid
extends System.Web.UI.WebControls.RangeValidator
{
protected boolean EvaluateIsValid()
{
// Get the value of the control to validate.
String controlValue = GetControlValidationValue(get_ControlToValidate());
// If no value was entered, show the validation error by returning false.
if (controlValue.Trim().get_Length() == 0) {
return false;
}
// Compare the ControlToValidate's value against the
// minimum and maximum values.
return Compare(controlValue, this.get_MinimumValue(),
System.Web.UI.WebControls.ValidationCompareOperator.
GreaterThanEqual,this.get_Type()) && Compare(controlValue,
this.get_MaximumValue(),System.Web.UI.WebControls.
ValidationCompareOperator.LessThanEqual,this.get_Type());
} //EvaluateIsValid
} //CustomRangeValidatorEvaluateIsValid
Community Additions
ADD
Show: