extract specific string in NSString

Question

i think it is a simple question but i dont know how to solve it.

i have a NSString that containes html content.

i want to extract some tags.

NSString *string=@"test some text <img src='http://www.xyz.com/a.jpg' > blah blah <a href='asdfg'>aaaa</a> bbbb cccc";

i want to take img & "a" tag into new string. then i will display it in UIWebView.

how can i parse it?

Will the string always be that simple or could it be any arbitrary HTML from which you need to extract img and a tags? — JeremyP, Oct 12 '10 at 15:31
i will just extract img, a and iframe tags into another string, then i will display the new string in a webview. — tester, Oct 12 '10 at 19:55

score 1 · Answer 1 · answered Oct 12 '10 at 13:27

The best way is to write a partial tag parser. This is not very difficult.

Another option is to simply find the position of src=' and then the position of the closing "`" and then take the string in between.

You can do this with NSString's rangeOfString: methods.

score 1 · Answer 2 · edited Feb 13 '21 at 14:28

1

You can use Regular Expressions, I have used this library to scrape web pages in the iPhone http://regexkit.sourceforge.net/RegexKitLite/index.html

edited Feb 13 '21 at 14:28

answered Oct 12 '10 at 13:28

GuidoMB

+1 regexkitlite is a godsend. I don't know why there isn't a native regex function in objective-c – Thomas Clayson Oct 12 '10 at 13:29
1

Don't use RegEx to parse HTML: http://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags/1732454#1732454 – Jasarien Oct 12 '10 at 13:31
1

@Thomas Clayson - there is: NSRegularExpression is in 4.0. – Jasarien Oct 12 '10 at 13:32

2 Answers2