regular expressions in java

[passion_to_be_free]

I am writing a javascript that will make an http request, sort through
the html for any links on the page, and then store them for future
processing.

To test things, I pasted html source code into my text editor, ran a
GREP search using the following regular expression:

(<a [^>]*href\s*=\s*")([^"]+)("[^>]*>)

And the appropriate links were highlighted correctly. I then
implemented this regular expression into my javascript. However, the
javascript only matched one out of 10 links on the page I was
searching. Can anyone

(a.) tell me what's wrong with my regular expression
(b.) suggest a better one?

Here's my javascript code. I've even tried it two ways (as you'll see
by the commented code):

// make the page request
var xmlhttp;

if (window.XMLHttp Request)
{
xmlhttp=new XMLHttpRequest( );
xmlhttp.open("G ET",querystring ,false);
xmlhttp.send(nu ll);

//just to verify I'm getting something back:
//document.write( xmlhttp.respons eText);
}

var htmltext = xmlhttp.respons eText;

//Method 1:
//create a pattern matcher and execute it
var reg = new RegExp("");
reg.compile('(< a class=l [^>]*href\s*=\s*")([^"]+)("[^>]*>)');
var searchresults = reg.exec(htmlte xt);

//Method 2:
//use the string.match() function
//var searchresults = htmltext.match( '(<a class=l
[^>]*href\s*=\s*")([^"]*)("[^>]*>)');

[Duncan Booth]

Your Subject line doesn't seem to have any relationship to your problem, so
I've changed it.

pa************* ***@hotmail.com wrote:

//Method 1:
//create a pattern matcher and execute it
var reg = new RegExp("");
reg.compile('(< a class=l [^>]*href\s*=\s*")([^"]+)("[^>]*>)');
var searchresults = reg.exec(htmlte xt);

Inside a string \s is simply another way to write s. If you want a
backslash in a string you must escape it.

Why are you using strings to create your regular expression at all? Why are
you trying to allow for spaces at a point where they aren't allowed?

var reg = /(<a class=l [^>]*href=")([^"]+)("[^>]*>)/;

should get you a bit further.

Final question, do you really need regular expressions here at all? You are
making a lot of assumptions about exactly how the element has been written:
no quotes round the class attribute, double quotes round the href
attribute, class appears before href. If you parse the responseText into an
HTML DOM then you can just use getElementsByTa gName('a') and then pick out
the ones with the right class. In other words, if you want to process HTML
you might be better loading it into an iframe rather than using
XMLHTTPRequest, or if you have control over what you are retrieving send
back XML instead of HTML.