In this VB.NET Email Validation example, method calls the Regex.IsMatch(String, String) method to verify that the string confirms to a regular expression pattern.
Imports System.Text.RegularExpressions
Public Class Form1
Private Sub btnCheck_Click(sender As System.Object, e As System.EventArgs) Handles btnCheck.Click
Dim emailaddress = txtEmail.Text
Dim pattern As String = "^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$"
Dim emailAddressMatch As Match = Regex.Match(emailaddress, pattern)
If emailAddressMatch.Success Then
'emailaddresscheck = True
MsgBox("Correct email ID", MsgBoxStyle.Information)
Else
'emailaddresscheck = False
MsgBox("Incorrect email ID", MsgBoxStyle.Exclamation)
End If
End Sub
End Class