FAQ Topic - How do I trim whitespace - LTRIM/RTRIM/TRIM?

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FAQ Topic - How do I trim whitespace - LTRIM/RTRIM/TRIM?
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Using Regular Expressions (JavaScript 1.2/JScript 4+) :

String.prototype.lTrim =
function()
{
return this.replace(/^\s+/,'');
}
String.prototype.rTrim =
function()
{
return this.replace(/\s+$/,'');
}
String.prototype.trim =
function()
{
return this.replace(/^\s+|\s+$/g,'');
}

or for all versions (trims characters ASCII<32 not true
"whitespace"):

function LTrim(str) {
for (var k=0; k<str.length && str.charAt(k)<=" " ; k++) ;
return str.substring(k,str.length);
}
function RTrim(str) {
for (var j=str.length-1; j>=0 && str.charAt(j)<=" " ; j--) ;
return str.substring(0,j+1);
}
function Trim(str) {
return LTrim(RTrim(str));
}

http://msdn.microsoft.com/library/de...63906a7353.asp

http://docs.sun.com/source/816-6408-10/regexp.htm

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FAQ server wrote:
> -----------------------------------------------------------------------
> FAQ Topic - How do I trim whitespace - LTRIM/RTRIM/TRIM?
> -----------------------------------------------------------------------
>
> Using Regular Expressions (JavaScript 1.2/JScript 4+) :
>
> String.prototype.lTrim =
> function()
> {
> return this.replace(/^\s+/,'');
> }
> String.prototype.rTrim =
> function()
> {
> return this.replace(/\s+$/,'');
> }
> String.prototype.trim =
> function()
> {
> return this.replace(/^\s+|\s+$/g,'');
> }

I have tested the following requirements to be available as of JScript
_3.1.3510_ (in standalone IE 4.01/WinNT [1]):

- Anonymous function expression
- String.prototype.replace()
- RegExp literal with `g' modifier, and without `i' modifier
- Replacing substrings matching against the aforementioned RegExp object

I have retrieved the JScript version information through ScriptEngine(),
ScriptEngineMajorVersion(), ScriptEngineMinorVersion(), and
ScriptEngineBuildVersion(), and tested several newer features (like
try...catch) to be *not* supported by that script engine. Therefore,
I am confident I got valid results.

I have updated http://PointedEars.de/scripts/es-matrix accordingly.

The FAQ should be updated as well.

PointedEars
___________
[1] http://tredosoft.com/Multiple_IE
--
realism: HTML 4.01 Strict
evangelism: XHTML 1.0 Strict
madness: XHTML 1.1 as application/xhtml+xml
-- Bjoern Hoehrmann

Thomas 'PointedEars' Lahn said the following on 8/23/2007 8:40 PM:
> FAQ server wrote:
>> -----------------------------------------------------------------------
>> FAQ Topic - How do I trim whitespace - LTRIM/RTRIM/TRIM?
>> -----------------------------------------------------------------------
>>
>> Using Regular Expressions (JavaScript 1.2/JScript 4+) :
>>
>> String.prototype.lTrim =
>> function()
>> {
>> return this.replace(/^\s+/,'');
>> }
>> String.prototype.rTrim =
>> function()
>> {
>> return this.replace(/\s+$/,'');
>> }
>> String.prototype.trim =
>> function()
>> {
>> return this.replace(/^\s+|\s+$/g,'');
>> }
>
> I have tested the following requirements to be available as of JScript
> _3.1.3510_ (in standalone IE 4.01/WinNT [1]):

<snip>

> The FAQ should be updated as well.

I have changed it locally to read JScript 3 although I don't think it
makes much difference.
--
Randy
Chance Favors The Prepared Mind
comp.lang.javascript FAQ - http://jibbering.com/faq/index.html
Javascript Best Practices - http://www.JavascriptToolbox.com/bestpractices/

FAQ Topic - How do I trim whitespace - LTRIM/RTRIM/TRIM? - Javascript