RegEx to count lines in a file

[bcamp1973]

I'm using jQuery to pull a file asynchronously. I want to then sum the total of lines in that file that begin with "/". The file is a cache manifest and looks something like this...

/path/to/file.jpg
/path/to/another/file.css

etc.

Is there a simple approach to this? I've been messing with regex to get it done and not having much luck...

[MartinRinehart]

You have either a simple or a non-trivial problem. I'll assume it's the former, you can get back if it's the latter.

/ - start of regex
^ - start of input
/ - end of input, so, escape it:
\/
. - any character
* repeated any number of times
$ - end of input
/ - end of regex

so:
var count = 0;
for ( var line in file ) {
if ( line.match( /^\/.*/ ) ) { count += 1; }
}

[clueful]

Something like this perhaps:

function count( str, re )
{
   var m = str.match( re );

   return m ? m.length : 0;
}

alert( count( myString, /(^|\r*\n)\//g ) );

[MartinRinehart]

That RE assumes your whole file is in a single string.

It uses the "g" suffix to match globally: /regex here/g

That regex finds either A or B where A is the start of the input and B is (zero or more returns, followed by a single newline) followed by the forward slash character.

Very slick. I will definitely use those thoughts.

[bcamp1973]

great stuff, thanks to you both!