Regex to Indent an XML File

Question

Is it possible to write a REGEX (search replace) that when run on an XML string will output that XML string indented nicely?

If so whats the REGEX :)

Answer 1

From this link:

  private static Regex indentingRegex=new Regex(@"\<\s*(?[\w\-]+)(\s+[\w\-]+\s*=\s*""[^""]*""|'[^']*')*\s*\>[^\<]*\<\s*/\s*\k\s*\>|\<[!\?]((?<=!)--((?!--\>).)*--\>|(""[^""]*""|'[^']'|[^>])*\>)|\<\s*(?/)?\s*[\w\-]+(\s+[\w\-]+\s*=\s*""[^""]*""|'[^']*')*\s*((/\s*)|(?))\>|[^\<]*", RegexOptions.ExplicitCapture|RegexOptions.Singleline);

  public static string IndentXml(string xml) {
        StringBuilder result=new StringBuilder(xml.Length*2);
        int indent=0;
        for (Match match=indentingRegex.Match(xml); match.Success; match=match.NextMatch()) {
              if (match.Groups["closing"].Success)
                    indent--;
              result.AppendFormat("{0}{1}\r\n", new String(' ', indent*2), match.Value);
              if (match.Groups["opening"].Success&&(!match.Groups["closing"].Success))
                    indent++;
        }
        return result.ToString();
  }