count linebreaks

[Jeff Thies]

I need a quick way to count linebreaks. This is slug slow:

function findLinebreaks( str) {
var re='/\r\n|\n|\r\|\f/g';
var i=0;
while(re.match( str)){
i++;}
return i;
}

Cheers,
Jeff

[Ivo]

Re: count linebreaks

"Jeff Thies" <nospam@nospam. net> wrote in message
news:2%Hec.5312 $l75.246@newsre ad2.news.atl.ea rthlink.net...[color=blue]
> I need a quick way to count linebreaks. This is slug slow:
>
> function findLinebreaks( str) {
> var re='/\r\n|\n|\r\|\f/g';
> var i=0;
> while(re.match( str)){
> i++;}
> return i;
> }
>
> Cheers,
> Jeff
>[/color]

What is wrong with
return str.split(/\r\n|\n|\r\|\f/)
possibly with an extra check for the last character on the last line?
HTH
Ivo

[Martin Honnen]

Re: count linebreaks



Jeff Thies wrote:
[color=blue]
> I need a quick way to count linebreaks. This is slug slow:
>
> function findLinebreaks( str) {
> var re='/\r\n|\n|\r\|\f/g';
> var i=0;
> while(re.match( str)){
> i++;}
> return i;
> }[/color]

What happends when you use a regular expression literal and only the
test method:

function countLineBreaks 1 (string) {
var pattern = /\r\n|\r|\n/g;
var count = 0;
while (pattern.test(s tring)) {
count++;
}
return count;
}

--

Martin Honnen

http://JavaScript.FAQTs.com/

[Jeff Thies]

Re: count linebreaks

The winner is:

return str.split(/\n|\f/).length;

much much much faster.

The \r\n part of my test caused problems with IE not counting blank lines.
The \f is for Macs.

Cheers,
Jeff[color=blue]
>
>
> Jeff Thies wrote:
>[color=green]
> > I need a quick way to count linebreaks. This is slug slow:
> >
> > function findLinebreaks( str) {
> > var re='/\r\n|\n|\r\|\f/g';
> > var i=0;
> > while(re.match( str)){
> > i++;}
> > return i;
> > }[/color]
>
> What happends when you use a regular expression literal and only the
> test method:
>
> function countLineBreaks 1 (string) {
> var pattern = /\r\n|\r|\n/g;
> var count = 0;
> while (pattern.test(s tring)) {
> count++;
> }
> return count;
> }
>
> --
>
> Martin Honnen
> http://JavaScript.FAQTs.com/
>[/color]