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]

"Jeff Thies" <no****@nospam.net> wrote in message
news:2%****************@newsread2.news.atl.earthli nk.net...

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

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]

Jeff Thies wrote:

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;
}

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

function countLineBreaks1 (string) {
var pattern = /\r\n|\r|\n/g;
var count = 0;
while (pattern.test(string)) {
count++;
}
return count;
}

--

Martin Honnen
http://JavaScript.FAQTs.com/

[Jeff Thies]

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

Jeff Thies wrote:

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;
}

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

function countLineBreaks1 (string) {
var pattern = /\r\n|\r|\n/g;
var count = 0;
while (pattern.test(string)) {
count++;
}
return count;
}

--

Martin Honnen
http://JavaScript.FAQTs.com/