Using Regular Expressions to replace HTML tags, except simple formatting

[AndiSmith]

Hi,

I'm adding some old database fields to view in our new C# .NET system with cascading stylesheets, and unfortunately the old data has HTML formatting in there which I would like to be removed for these pages as this will be mainly driven by the CSS.

I know the Regular Expression to remove all HTML tags, but would anybody happen to know a regular expression that could replace all HTML tags except bold, italic, underline and breaking space (<b>,<u>,<i>,<br />) as I'd still like to give users the opportunity to use these tags?

Thanks,
Andi

[AndiSmith]

If anyone's interested, I decided to use the following Pattern, which removes each HTML element explicitly except the ones I want:

Pattern = @"(<\/?)(?i:(?<element>a(bbr|cronym|ddress|pplet|rea)?|" + @"base(font)?|bdo|big|blockquote|body|button|c(apt ion|enter|ite|(o(de|l(group)?)))|" + @"d(d|el|fn|i(r|v)|l|t)|em|f(ieldset|o(nt|rm)|rame (set)?)|h([1-6]|ead|r|tml)|iframe|" + @"img|in(put|s)|sindex|kbd|l(abel|egend|i(nk)?)|m( ap|e(nu|ta))|no(frames|script)|o(bject|"+ @"l|pt(group|ion))|p(aram|re)?|q|s(amp|cript|elect |mall|pan|t(r(ike|ong)|yle)|u(b|p))|" +
@"t(able|body|d|extarea|foot|h|itle|r|t)|ul|var))( \s(?<attr>.+?))*>";