Valadaing an email address in a text box

[tedglen2]

Does any one have any sample code on how i can Valadate an email address. Thanks

[jmcilhinney]

You'd use regular expressions to validate it something like this:

Private Const EMAIL_PATTERN As String = "^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$"
 
    Private Sub emailText_Validating(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles emailText.Validating
        Dim address As String = Me.emailText.Text.Trim()
 
        'Check that the e-mail address field is either empty or contains a valid e-mail address.
        If address <> String.Empty AndAlso Not Regex.IsMatch(address, EMAIL_PATTERN) Then
            Me.emailText.HideSelection = False
            Me.emailText.SelectAll()
 
            MessageBox.Show("Please enter a valid e-mail address.", _
                            Application.ProductName, _
                            MessageBoxButtons.OK, _
                            MessageBoxIcon.Error)
 
            Me.emailText.HideSelection = True
            e.Cancel = True
        End If
    End Sub

That's taken from a project I'm working on at this very second. Note that that pattern is relatively basic. It will allow things like "[email protected]". If you truly want to validate an e-mail address stringently, the O'Reilly book "Mastering Regular Expressions" provides a pattern to do it that is more than a page long.

[Shuja Ali]

This works properly for me
^[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]$

[tedglen2]

hi, i cant get this to work it says Regex is not declared ?

[MrGTI]

try adding this to the top of the page:

Imports System.Text.RegularExpressions