Behaviour of string.split()

I understand that string.split() should produce an array from a
string. However when I use the following script the type of the result
is indeed an object but the array elements are undefined. Why?

var strTest = '1,2,3,4';
var aryTest = strTest.split();
alert(typeof aryTest + " " + aryTest[2]);

Thanks in advance.

On Aug 13, 11:59 am, Steve wrote:

I understand that string.split() should produce an
array from a string. However when I use the
following script the type of the result is indeed
an object but the array elements are undefined. Why?

var strTest = '1,2,3,4';
var aryTest = strTest.split();
alert(typeof aryTest + " " + aryTest[2]);

If you do not provide the first ("Separator") argument to -
String.prototype.split - it will return a one element array with first
(zero index) element containing a string that is equivalent to the
original string. Thus - arryTest[2] - would be expected to result in
the undefined value as the - length - of - arrayTest - will be one and
its only existing 'array index' property is '0'.

var strTest = '1,2,3,4';
var aryTest = strTest.split();
alert(typeof aryTest + " *" + aryTest[2]);

Hey, you didn't tell your JavaScript VM where to split! Try this:

var strTest = '1,2,3,4';
var aryTest = strTest.split(',');
alert(typeof aryTest + " " + aryTest[2]);

Looks better?

virtuPIC

--
Airspace V - international hangar flying!
http://www.airspace-v.com/ggadgets for tools & toys

On Aug 13, 1:26 pm, virtuPIC <WebMas... (AT) airspace-v (DOT) com> wrote:

var strTest = '1,2,3,4';
var aryTest = strTest.split();
alert(typeof aryTest + " " + aryTest[2]);

Hey, you didn't tell your JavaScript VM where to split! Try this:

var strTest = '1,2,3,4';
var aryTest = strTest.split(',');
alert(typeof aryTest + " " + aryTest[2]);

Looks better?

Yes it does.

However according to the material I have read, including the Rhino,
the comma is the default. But I should have thought of that anyway.

Many Thanks,

Steve.

On 2008-08-13, Gregor Kofler <usenet (AT) gregorkofler (DOT) at> wrote:

Steve meinte:
However according to the material I have read, including the Rhino,
the comma is the default. But I should have thought of that anyway.

Read again. Mozilla doesn't state a "default separator". Instead
"If separator is omitted, the array returned contains one element
consisting of the entire string." [1]
I suppose other ECMAScript derivates behave equally.

Probably the OP is thinking of the inverse operation, Array.join()
where Flanagan's O'Reilly book says "if the argument is omitted,
a comma is used."

Regards, Peter Billam

--
Peter Billam www.pjb.com.au www.pjb.com.au/comp/contact.html