JS Five ways to remove space before and after a string

First: cyclic check replacement
[JavaScript]
For the user to invoke
function Trim (s) {
Return TrimRight (Trimleft (s));
}
Remove the left blank
function Trimleft (s) {
if (s = = null) {
Return "";
}
var whitespace = new String ("\t\n\r");
var str = new String (s);
if (Whitespace.indexof (Str.charat (0))! =-1) {
var j=0, i = str.length;
while (J < i && Whitespace.indexof (Str.charat (j))! =-1) {
j + +;
}
str = str.substring (j, I);
}
return str;
}
Remove the blank www.2cto.com on the right
function TrimRight (s) {
if (s = = null) return "";
var whitespace = new String ("\t\n\r");
var str = new String (s);
if (Whitespace.indexof (Str.charat (str.length-1)) =-1) {
var i = str.length-1;
while (i >= 0 && whitespace.indexof (str.charat (i))! =-1) {
i--;
}
str = str.substring (0, i+1);
}
return str;
}
The second type: regular replacement
[JavaScript]
<script language= "JavaScript" >
<!--
String.prototype.Trim = function ()
{
Return This.replace (/(^\s*) | ( \s*$)/g, "");
}
String.prototype.LTrim = function ()
{
Return This.replace (/(^\s*)/g, "");
}
String.prototype.RTrim = function ()
{
Return This.replace (/(\s*$)/g, "");
}
-
</SCRIPT>
The third type: using jquery
[JavaScript]
$.trim (str)
The internal implementation of jquery is:
[JavaScript]
function Trim (str) {
Return Str.replace (/^ (\s|\u00a0) +/, "). Replace (/(\S|\U00A0) +$/, ');
}
Fourth: Use of Motools
[JavaScript]
function Trim (str) {
Return Str.replace (/^ (\s|\xa0) +| ( \S|\XA0) +$/g, ");
}
Fifth: Clipping string mode
[JavaScript]
function Trim (str) {
str = str.replace (/^ (\s|\u00a0) +/, ");
for (var i=str.length-1; i>=0; i--) {
if (/\s/.test (Str.charat (i))) {
str = str.substring (0, i+1);
Break
}
}
return str;
}
The fifth method tested is most efficient when working with long strings.


Excerpt from executing the Dream code

JS Five ways to remove space before and after a string