Adding extension method to string
Imports System Imports System.Linq Imports System.Runtime.CompilerServices Module Module1 Sub Main() Dim s As String = "this is a test" Console.WriteLine(s.SpaceToUnderscore()) End Sub End Module <Extension()> _ Public Class Extensions <Extension()> _ Public Shared Function SpaceToUnderscore(ByVal source As String) As String Dim cArray As Char() = source.ToCharArray() Dim result As String = String.Empty For Each c As Char In cArray If Char.IsWhiteSpace(c) Then result = result & "_" Else result = result & c End If Next Return result End Function End Class