Visual Basic .NET replace tab characters

From Regex Regular Expression Encyclopedia

This wiki is for replacing tab characters in a string with a different character using Visual Basic .NET. In this recipe, we use a pipe (|) to replace the tab.

[edit] code

Imports System
Imports System.IO
Imports System.Text.RegularExpressions
Public Class Recipe
    Private Shared _Regex As Regex = New Regex("\t")
    Public Sub Run(ByVal fileName As String)
        Dim line As String
        Dim newLine As String
        Dim sr As StreamReader = File.OpenText(fileName)
        WORDS AND TEXT
        line = sr.ReadLine
        While Not line Is Nothing
                               newLine = _Regex.Replace(line, "|")
                               Console.WriteLine("New string is: '{0}', original was: '{1}'", _
                                newLine, _
                                line))
                               line = sr.ReadLine
                           End While
                           sr.Close()
                       End Sub
    Public Shared Sub Main(ByVal args As String())
        Dim r As Recipe = New Recipe
        r.Run(args(0))
    End Sub
End Class

[edit] How It Works

Breaking the recipe down yields simply the following:

By default, the regular expression object in the .NET Framework replaces each occurrence of the text that matches the search regex. However, the VBScript and JavaScript regular expres- sion objects work differently because an option must be specified to replace each match. You can find more about these options in the “Syntax Overview” section of this book.

[edit] Variations

Since this is such a simple recipe, it has an extensive number of variations. You could replace the character class representing a tab with other character classes, especially the \s character class. The JavaScript variation /\s/g would replace each instance of whitespace with |.

One variation on the previous recipe is to use a qualifier after the character class to replace more than one instance of a tab at once. For instance, if you want to replace two tabs, you could use something such as /\t{2}/g in the JavaScript recipe.