How to: Parse E-mail Addresses in Visual Basic
This example demonstrates a simple regular expression for parsing an e-mail address.
Example
This example uses the regular expression (\S+)@([^\.\s]+)(?:\.([^\.\s]+))+, which means:
Set of one or more non-space characters (captured), followed by
The character "@", followed by
Set of one or more non-space and non-period characters (captured), followed by
One or more of the following:
The character ".", followed by
Set of one or more non-space and non-period characters (captured).
The regular expression's Match method returns a Match object that contains information about what part of the input string the regular expression matches.
''' <summary>
''' Parses an e-mail address into its parts.
''' </summary>
''' <param name="emailString">E-mail address to parse.</param>
''' <remarks> For example, this method displays the following
''' text when called with "someone@mail.contoso.com":
''' User name: someone
''' Address part: mail
''' Address part: contoso
''' Address part: com
''' </remarks>
Sub ParseEmailAddress(ByVal emailString As String)
Dim emailRegEx As New Regex("(\S+)@([^\.\s]+)(?:\.([^\.\s]+))+")
Dim m As Match = emailRegEx.Match(emailString)
If m.Success Then
Dim output As String = ""
output &= "User name: " & m.Groups(1).Value & vbCrLf
For i As Integer = 2 To m.Groups.Count - 1
Dim g As Group = m.Groups(i)
For Each c As Capture In g.Captures
output &= "Address part: " & c.Value & vbCrLf
Next
Next
MsgBox(output)
Else
MsgBox("The e-mail address cannot be parsed.")
End If
End Sub
This example requires that you use the Imports statement to import the System.Text.RegularExpressions namespace. For more information, see Imports Statement (.NET Namespace and Type).
See Also
Tasks
How to: Verify That Strings Are in Valid E-Mail Format