replace a string using wildcards

Question

I have a piece of html code that I want to wipe out some style parts, I know I need to regex but I don't know how to generate the regex or even how to apply it in my c# code. Below is the sample of original string:

<p style="color: #000000; text-transform: none; letter-spacing: normal; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; word-spacing: 0px; white-space: normal; font-size-adjust: none; font-stretch: normal; -webkit-text-stroke-width: 0px;">

And here is the output that I wish to get after a replace operation:

<p>

I want to get rid of the style attribute. And I need to do this for all occurances of <p ...>

There exist tons of examples about this kind of jobs, but I really got confused about this. So any clue on solution would be great. Thanks in advance.

Check the accepted answer: http://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags - consider using an HTML Parser rather than regex — Jamiec, Aug 14 '13 at 09:30

Jerry · Accepted Answer · 2013-08-14T10:30:20.233

3

You really find a regex tutorial (example) to learn how matches work, then replacements will be easier...

string output = Regex.Replace(input, @"(?<=<p)[^>]+", "");

See demo.

To remove only the style attribute, you could perhaps use this:

string output = Regex.Replace(input, @"(?<=<p)\s*style=""[^""]+""", "");

Note that this won't work if the style attribute is immediately after the <p (with any number of spaces).

Updated demo.

To remove the attribute style anywhere in the html, you can perhaps use (a bit safer than the previous one maybe):

string output = Regex.Replace(input, @"(?<=<p)([^>]*?)\s*style=""[^"">]+""", "$1");

Reupdated demo.

edited Aug 14 '13 at 10:30

answered Aug 14 '13 at 09:33

Jerry

70,495
13
100
144

1

This is a good start, but wipes out *every* attribute not just the style attribute. Plug `
` into it
– Jamiec Aug 14 '13 at 09:42
for now I just need to get rid of all attributes, but sure it would be good to learn removing specific attributes. – Tolga Evcimen Aug 14 '13 at 10:05
@TolgaEvcimen Sorry to having taken some more time to have one regex to remove the style attribute anywhere in the p tag. I just updated the regex to be able to do this. – Jerry Aug 14 '13 at 10:33
I already put your previous regex in action, and it works fine right now. I'll look into the tutorial that you suggest. I hope I won't be posting questions about regex matching again thanks to you:) – Tolga Evcimen Aug 14 '13 at 11:08
@TolgaEvcimen That's okay to post regex questions as long as there's the attempt and/or effort shown. And it's usually best with what should happen and what shouldn't happen to make sure everyone understands your question :) You're welcome! – Jerry Aug 14 '13 at 11:12

score 0 · Answer 2 · edited Aug 14 '13 at 09:43

Not sure how to do it in c#, but using a general example in bash regex, I would do:

echo "$pattern" | sed -r 's/(<p).*(>)/\1\2/'

Where:

(<p) ----- Captures the opening bracket with p
.*   ----- Anything inbetween up to the next ">"
()   ----- Captures the closing bracket
\1\2 ----- Gives you back the two captured things, 
           in this order, with no space inbetween

Hope it helps, but again, you need to look up for replacing in c# yourself.

replace a string using wildcards

2 Answers2