Asp. NET regular replace an IMG src/href in HTML tags

As the title, a long string of strings may include multiple <a href= "" > and

You want to replace all the link addresses in href= "and src=" with an address, but keep the file names that follow.

such as href= "File://a/11.doc"-----> href = "Http://www.a.com/a/11.doc"
src= "File://a/22.gif"-----> href = "http://www.a.com/a/22.gif"

There may be more than one such address in the string.

Solving method

String output = Regex.Replace (Input, "(? is) (?<=< (a|img) \b.*?" ( HREF|SRC) = "") file://"," http://www.a.com/");