IValidator.Validate Method
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
When implemented by a class, evaluates the condition it checks and updates the IsValid property.
public:
void Validate();
public void Validate ();
abstract member Validate : unit -> unit
Public Sub Validate ()
Examples
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.
<!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>IValidator Example demonstrating IsValid & ErrorMessage</title>
<script language="C#" runat="server">
void Button_Click(Object sender, EventArgs e)
{
// Generating the random number.
Random rand_s = new Random();
myCompareValidate.ValueToCompare = rand_s.Next(1, 10).ToString();
// Setting the ErrorMessage.
myCompareValidate.ErrorMessage="Try Again!!";
myCompareValidate.Validate();
// Check for Validity of control.
if ((myCompareValidate.IsValid) && (myTextBox.Text != ""))
{
labelOutput.Text = "You guessed correctly!!";
labelOutput.ForeColor = System.Drawing.Color.Blue;
}
else
{
labelOutput.Text = "You guessed poorly";
labelOutput.ForeColor = System.Drawing.Color.Black;
}
labelOutput.Text += "<br /><br />" + "The number is: " +
myCompareValidate.ValueToCompare;
}
</script>
</head>
<body>
<form runat="server" id="myForm">
<h3>IValidator Example demonstrating IsValid & ErrorMessage</h3>
<h5>Guess!! a number between 1 and 10 :</h5>
<asp:TextBox id="myTextBox" runat="server" />
<asp:CompareValidator id="myCompareValidate"
ControlToValidate="myTextBox" ValueToCompare="0"
EnableClientScript="False" Type="Integer" Text="*"
runat="server" />
<br />
<asp:Button Text="Submit" OnClick="Button_Click" runat="server" />
<br />
<asp:Label id="labelOutput" runat="server" />
<br />
<asp:ValidationSummary id="Summary1" runat="server" />
</form>
</body>
</html>
<!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>IValidator Example demonstrating IsValid & ErrorMessage</title>
<script language="VB" runat="server">
Sub Button_Click(sender As [Object], e As EventArgs)
' Generating a random number.
Dim rand_s As New Random()
myCompareValidate.ValueToCompare = rand_s.Next(1, 10).ToString()
' Set the ErrorMessage.
myCompareValidate.ErrorMessage = "Try Again!!"
myCompareValidate.Validate()
' Check for Validity of control.
If myCompareValidate.IsValid And myTextBox.Text <> "" Then
labelOutput.Text = "You guessed correctly!!"
labelOutput.ForeColor = System.Drawing.Color.Blue
Else
labelOutput.Text = "You guessed poorly"
labelOutput.ForeColor = System.Drawing.Color.Black
End If
labelOutput.Text += "<br /><br />" + "The number is: " + _
myCompareValidate.ValueToCompare
End Sub 'Button_Click
</script>
</head>
<body>
<form runat="server" id="myForm">
<h3>IValidator Example demonstrating IsValid & ErrorMessage</h3>
<h5>Guess!! a number between 1 and 10:</h5>
<asp:TextBox id="myTextBox" runat="server" />
<asp:CompareValidator id="myCompareValidate"
ControlToValidate="myTextBox" ValueToCompare="0"
EnableClientScript="False" Type="Integer" Text="*"
runat="server" />
<br />
<asp:Button Text="Submit" OnClick="Button_Click" runat="server" />
<br />
<asp:Label id="labelOutput" runat="server" />
<br />
<asp:ValidationSummary id="Summary1" runat="server" />
</form>
</body>
</html>
Applies to
See also
Feedback
https://aka.ms/ContentUserFeedback.
Binnenkort beschikbaar: In de loop van 2024 zullen we GitHub-problemen geleidelijk uitfaseren als het feedbackmechanisme voor inhoud en deze vervangen door een nieuw feedbacksysteem. Zie voor meer informatie:Feedback verzenden en weergeven voor