How to Count the number of lines?

[Anz]

Is there any javascript function for counting the number of lines
inside a text area ?

 

[RoLo]

Is there any javascript function for counting the number of lines
inside a text area ?

try:
a.value.split("\n").length

 

[Bart Van der Donck]

try:
a.value.split("\n").length

I'm afraid it's not that simple. The number of lines in a textarea
does not necessarily represent the number of newline characters. You
are right that your solution should work for a <textarea wrap="off">
in MSIE and FireFox, although that will not qualify as valid X/HTML.

The original poster should first be clear whether or not the text in
his <textarea> should wrap.

1) If yes:
Read out the number of columns with [obj].cols as to split the content
accordingly, but only if the wrapped string must be considered as
multiple lines. In the other case, use a.value.split("\n").length.

2) If no:
Use a.value.split("\n").length.

In both in cases, the textarea must be set with the right wrap
attributes/CSS as to achieve a maximum browser compatibility.

Hope this helps,

 

[Thomas 'PointedEars' Lahn]

Is there any javascript function for counting the number of lines
inside a text area ?

As for actual lines, independent of presentation:

textarea.value.split(/\r?\n|\r/).length


PointedEars

 

[Evertjan.]

Thomas 'PointedEars' Lahn wrote on 01 jul 2008 in comp.lang.javascript:

As for actual lines, independent of presentation:

textarea.value.split(/\r?\n|\r/).length

textarea.value.split(/\r?\n|\r/).length + 1

 

[Dr J R Stockton]

In comp.lang.javascript message <cd27072c-761f-4e82-a475-fd08860157c0@v1
g2000pra.googlegroups.com>, Tue, 1 Jul 2008 00:39:12, Anz

Is there any javascript function for counting the number of lines
inside a text area ?

In addition to what others have written, ISTM that there is a question
of whether blank lines within, before, or after non-blank lines should
be counted.

 

[Evertjan.]

Dr J R Stockton wrote on 01 jul 2008 in comp.lang.javascript:

In comp.lang.javascript message


In addition to what others have written, ISTM that there is a question
of whether blank lines within, before, or after non-blank lines should
be counted.

.... where a blank line not always is an empty line.


===================================
<textarea id=t>



qqq

sss

www

</textarea>

<script type='text/javascript'>

var r;
var t = document.getElementById('t');

r = t.value.split(/\n/).length;
alert(r); // 9
r = t.value.split(/\n*/).length;
alert(r); // 18
r = t.value.split(/[\r\n]+/).length;
alert(r); // 3
r = t.value.split(/\n[\r\n]*/).length;
alert(r); //4

</script>
==================================

18 ???

What is happening here [IE7]?

;-)

 

[Bart Van der Donck]

<textarea id=t>

qqq

sss

www

</textarea>

<script type='text/javascript'>

var r;
var t = document.getElementById('t');

r = t.value.split(/\n/).length;
alert(r); // 9
r = t.value.split(/\n*/).length;
alert(r); // 18
r = t.value.split(/[\r\n]+/).length;
alert(r); // 3
r = t.value.split(/\n[\r\n]*/).length;
alert(r); //4

</script>
==================================

18  ???

What is happening here [IE7]?

In your example,

t.value.split(/\n*/).length

is the same as

t.value.length

minus the number of newlines in 't', because a split on '\n*' can be
semantically read as "splitting on a newline that is repeated zero or
more times".