Imports System
Public Module SubstringBetweenTwoSubstrings_VB
Function SubstringBetweenTwoSubstrings(str As String, suba As String, subb As String) As String
Dim posA As Integer = str.IndexOf(suba)
Dim posB As Integer = str.LastIndexOf(subb)
If posA = -1 Then
Return ""
End If
If posB = -1 Then
Return ""
End If
Dim IndexEndSuba As Integer = posA + suba.Length
If IndexEndSuba >= posB Then
Return ""
End If
Return str.Substring(IndexEndSuba, posB - IndexEndSuba)
End Function
Sub Main()
Dim str As String = "VB.NET:C C++:Java"
Console.WriteLine(SubstringBetweenTwoSubstrings(str, "NET", "Java"))
End Sub
End Module
' run:
'
' :C C++:
'