How do I remove trailing whitespace using a regular expression?

Question

I want to remove trailing white spaces and tabs from my code without removing empty lines.

I tried:

\\s+$

and:

([^\\n]         


        

Answer 1

The platform is not specified, but in C# (.NET) it would be:

Regular expression (presumes the multiline option - the example below uses it):

    [ \t]+(\r?$)

Replacement:

    $1

---

For an explanation of "\r?$", see Regular Expression Options, Multiline Mode (MSDN).

Code example

This will remove all trailing spaces and all trailing TABs in all lines:

string inputText = "     Hello, World!  \r\n" +
                   "  Some other line\r\n" +
                   "     The last line  ";
string cleanedUpText = Regex.Replace(inputText,
                                     @"[ \t]+(\r?$)", @"$1",
                                     RegexOptions.Multiline);