Replace string with matching pattern using Regex

Question

I want to add a <span></span> to each of the tag in the following XML. I would like to use C# regular expression like this.

Regex.Replace(xml, @"<*>", @"<span>" + @"<*>" + "</span>")

Original XML:

<div id="Content">
  <p>1</p>
  <h2>1</h2>
  <h2>2</h2>
</div>

Modified XML

<span><div id="Content"></span>
  <span><p></span>1<span></p></span>
  <span><h2></span>1<span></h2></span>
  <span><h2></span>2<span></h2></span>
<span></div></span>

Answer 1

I suggest to avoid using regex with xhtml, since it's well known that there are better tools. You could use xml parser, xquery, xpath, etc.

However, if you still have to use or want to use regex then you have to use capturing groups and also use a non greedy regex. You can use this:

(<.*?>)

working demo

Answer 2

Here is a working example of how to achieve this more or less safe:

var xml = "<div id=\"Content\">\r\n  <p>1</p>\r\n  <h2>1</h2>\r\n  <h2>2</h2>\r\n</div>";
var result = Regex.Replace(xml, @"<[^>]+?>", @"<span>$&</span>");

The regex used is <[^>]+?> that just matches < , then anything that is not > up to > .

Output:

Answer 3

How about this

  string input = "<div id=\\"Content\\">" + "<p>1</p>" + "<h2>1</h2>" + "<h2>2</h2>" + "</div>"; string pattern = @"(</?\\w+>)"; string output = Regex.Replace(input, pattern, "<span>$1</span>"); output = "<span>" + output + "</span>";​