Imports System
Public Module Module1
Function StringAfter(str As String, a As String) As String
Dim posA As Integer = str.LastIndexOf(a)
If posA = -1 Then
Return ""
End If
If posA + a.Length >= str.Length Then
Return ""
End If
Return str.Substring(posA + a.Length)
End Function
Sub Main()
Dim str As String = "VB.NET:C C++:Java"
Console.WriteLine(StringAfter(str, "NET"))
End Sub
End Module
' run:
'
' :C C++:Java
'