Multiple string delimiters - vb.net

Question

I'm a total beginner in the VB language and I have a string in the format:
Smith, Alex (asmith#gmail.com)
I'm attempting to isolate "asmith" from this string. I'm assuming that we would have to split at the "(" and then at the "#" and obtain the 1st index?
Any help is appreciated.

Answer 1

I'm assuming that we would have to split at the "(" and then at the "#" and obtain the 1st index?
Your approach is correct. A literal translation of your algorithm to VB.NET would be:
Dim firstPartOfMailAddress = text.Split("("c)(1).Split("#"c)(0)
Explanation:
"("c is a character literal. Split expects a character, not a string (that would be "(").
Arrays are zero-based in VB.NET and indexed using the (...) operator. Thus, you take the second part (1) of the first split and the first part (0) of the second split.
Notes:
This code does not include any error handling and will fail horribly if the text does not contain the character (.
An alternative would be to extract the value using a regular expression, but if your are new to the language, splitting is a much easier option.

Answer 2

Here is an option for you:
Dim input = "Smith, Alex (asmith#gmail.com)"
Dim output= input.Split("("c, "#"c)(1)

Answer 3

use class :
Imports System.Globalization
Imports System.Text.RegularExpressions
Public Class RegexUtilities
Dim invalid As Boolean = False
Public Function IsValidEmail(strIn As String) As Boolean
invalid = False
If String.IsNullOrEmpty(strIn) Then Return False
' Use IdnMapping class to convert Unicode domain names.
Try
strIn = Regex.Replace(strIn, "(#)(.+)$", AddressOf Me.DomainMapper,
RegexOptions.None, TimeSpan.FromMilliseconds(200))
Catch e As RegexMatchTimeoutException
Return False
End Try
If invalid Then Return False
' Return true if strIn is in valid e-mail format.
Try
Return Regex.IsMatch(strIn,
"^(?("")("".+?(?<!\\)""#)|(([0-9a-z]((\.(?!\.))|[-!#\$%&'\*\+/=\?\^`\{\}\|~\w])*)(?<=[0-9a-z])#))" +
"(?(\[)(\[(\d{1,3}\.){3}\d{1,3}\])|(([0-9a-z][-\w]*[0-9a-z]*\.)+[a-z0-9][\-a-z0-9]{0,22}[a-z0-9]))$",
RegexOptions.IgnoreCase, TimeSpan.FromMilliseconds(250))
Catch e As RegexMatchTimeoutException
Return False
End Try
End Function
Private Function DomainMapper(match As Match) As String
' IdnMapping class with default property values.
Dim idn As New IdnMapping()
Dim domainName As String = match.Groups(2).Value
Try
domainName = idn.GetAscii(domainName)
Catch e As ArgumentException
invalid = True
End Try
Return match.Groups(1).Value + domainName
End Function
End Class
and use code in form and customzition :
Dim util As New RegexUtilities()
Dim emailAddresses() As String = {"david.jones#proseware.com", "d.j#server1.proseware.com",
"jones#ms1.proseware.com", "j.#server1.proseware.com",
"j#proseware.com9", "js#internal#proseware.com",
"j_9#[129.126.118.1]", "j..s#proseware.com",
"js*#proseware.com", "js#proseware..com",
"js#proseware.com9", "j.s#server1.proseware.com",
"""j\""s\""""#proseware.com", "js#contoso.中国"}
For Each emailAddress As String In emailAddresses
If util.IsValidEmail(emailAddress) Then
Console.WriteLine("Valid: {0}", emailAddress)
Else
Console.WriteLine("Invalid: {0}", emailAddress)
End If
Next