Custom Validator
in ASP.NET:
In
this article we will learn how to use custom validator in ASP.Net Applications.
I will Use Custom Validator OnServerValidate Event and
perform validation on Server Side in ASP.Net using C# and VB.Net.
Description:
In
previous articles I have explained Error: ASP.NET:
Bind or Populate Form View Data control with data from SQL database using c#
& vb.net And
RegEx:
Validate Email Id on server Side using RegEx in ASP.NET .
Demo:
In this example I will validate TextBox control and
check whether entered Email Id is Valid or not. I will use OnServerValidate Event of custom validator.
Design your Page i.e. Design Section:
Enter Email:<asp:TextBox ID="txtEmail" runat="server" Width="200px"></asp:TextBox>
<br />
<br />
<asp:Button ID="btnEmail" runat="server" Text="Validate Email" />
<br />
<asp:CustomValidator ID="CustomValidator1" runat="server"
ErrorMessage="Email Id Is
not Valid"
OnServerValidate="IsEmailValid"
ClientValidationFunction="" ForeColor="#990000">
</asp:CustomValidator>
|
When
we press the button, OnServerValidate Event of custom validator will be handled. In this Event handler I have
used Regular Expression to validate data of text box.
We will validate the data using IsMatch()
method of Regular Expression RegEx.
Result of IsMatch() method i.e.
True or False, will be passed to Isvalid property of ServerValidateEventArgs. If
isvalid property is false then error message will be displayed otherwise Email
Id is Valid.
Asp.Net Code:
Using C#:
public void IsEmailValid(object sender, ServerValidateEventArgs e)
{
string strRegex = "^([a-zA-Z0-9_\\-\\.]+)@((\\[[0-9]{1,3}" + "\\.[0-9]{1,3}\\.[0-9]{1,3}\\.)|(([a-zA-Z0-9\\-]+\\" + ".)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\\]?)$";
Regex re = new Regex(strRegex);
e.IsValid =
re.IsMatch(txtEmail.Text);
}
|
Using Vb.net:
Public Sub
IsEmailValid(sender As Object, e As ServerValidateEventArgs)
Dim strRegex As String = "^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}" + "\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\" + ".)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$"
Dim re As New Regex(strRegex)
e.IsValid = re.IsMatch(txtEmail.Text)
End Sub
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In
this section we have learned how to use Custom validator in ASP.NET. if you
have any query then you can ask by leaving your query in comment section.
