Email validation control or code for VB.Net 2005.

Question

I am developing a windows application using VB.Net 2005.
One of my forms contains a textbox for entering email id. I want to validate its patterns i.e. It should have @, atleast one ".", etc.
In asp.net we have validation control for this.
But how to do it in VB.Net 2005.

Answer 1

Hi,

using Regular expressions you can do that.

 

see

 http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=817098&SiteID=1

 

Thanks,

Ch.T.Gopi Kumar.

Answer 2

Could you please tell me the namespace which I have to import for using regex.

Answer 3

Harsh wrote:

Could you please tell me the namespace which I have to import for using regex.

It's System.Text.RegularExpressions

 

see http://msdn2.microsoft.com/en-us/library/system.text.regularexpressions.regex.aspx

 

Thanks,

Ch.T.Gopi Kumar.

Answer 4

Hi I tried to use following code -

Imports System.Text.RegularExpressions

 

In one of my functions-

If txtEmail_1.Text <> "" Then

    Dim rex As Match = Regex.Match(Trim(txtEmail_1.Text), "[a-z0-9._]*@[a-z0-9_]*(\.[a-z0-9_]{2,4}){4}", RegexOptions.IgnoreCase)

    If rex.Success = False Then

            MessageBox.Show("Please Enter a valid Email-Address 1", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)

            txtEmail_1.Focus()

            Exit Function

    End If

End If

 

But it is always giving rex.success as false.

I entered correct email also still it is false.

Please tell me whether the compare condition is correct or not

Answer 5

Hi,

I've found one more good link,consisting the predefined regular expressions for currency,e-mail,zip code etc at

 

http://msdn2.microsoft.com/en-us/library/ms998267.aspx

 

So ,using the e-mail validation expression given in the above page,

your code would become as follows

 

If txtEmail_1.Text <> "" Then Dim rex As Match = Regex.Match(Trim(txtEmail_1.Text), "^([0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\w]*[0-9a-zA-Z]\.)+[a-zA-Z]{2,3})$", RegexOptions.IgnoreCase)     If rex.Success = False Then             MessageBox.Show("Please Enter a valid Email-Address 1", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)             txtEmail_1.Focus()             Exit Function     End If End If

 

This works fine.

 

Thanks,

Ch.T.Gopi Kumar.

Answer 6

Thanks

Answer 7

imports.system.text.regularexpressions

                   ]

                                     frm:lucky(btech)

Answer 8

 

Answer 9

what is web page desgine?

Answer 10

 

th u

Answer 11

 

means of listbox

Answer 12

 

listbox created

Answer 13

hi i got ur email thanks for help but wat is a data type of "MATCH" reply me soon

 

 

Answer 14

 

ok i got it sorry

Answer 15

thanks for ur help it is very use full to me but can u give me the string which provide ( . ) Dot also in the fisrt name of email address for  user

 

i am waiting for your reply

 

 

 

 

Answer 16

u sended me this string like

 

 

Dim rex As Match = Regex.Match(Trim(pobjSender.ValueText), "^([0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\w]*[0-9a-zA-Z]\.)+[a-zA-Z]{2,3})$", RegexOptions.IgnoreCase)

 

 

 

"^([0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\w]*[0-9a-zA-Z]\.)+[a-zA-Z]{2,3})$"

 

Answer 17

Can u plz explain this code.
Meas for what purpose * is used before @
What is the meaning of (,),{,} bracks....


Thank u..

Answer 18

Sorry for late reply i hope still this help you .

this will give all string manipulation

 

http://www.devarticles.com/c/a/VB.Net/Regular-Expressions-in-.NET/1/

Answer 19

You can also try this Ultimate Email Validator component.

Answer 20

Imports System.Text.RegularExpressions

Public Class Form1

Private Sub btnEmailCheck_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEmailCheck.Click

 Dim st As String

st = "^([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 reg As New Regex(st)

If reg.IsMatch(txtEmail.Text) Then

 MessageBox.Show("Email Valid")

Else

 MessageBox.Show("Email Not Valid")

 End If

End Sub

End Class

---

SChahal

Answer 21

good help, thanks