str为要去除空格的字符串:
去除所有空格:
str = str.replace(/\s+/g,”");
去除两头空格:
str = str.replace(/^\s+|\s+$/g,”");
去除左空格: phperz~com
str=str.replace( /^\s*/, ”); phperz.com
去除右空格:

str=str.replace(/(\s*$)/g, “”); www.phperz.com
SCRIPT LANGUAGE=”JavaScript”>
<!–
// Trim() , Ltrim() , RTrim()
String.prototype.Trim = function()
{
return this.replace(/(^\s*)|(\s*$)/g, “”);
}
String.prototype.LTrim = function()
{
return this.replace(/(^\s*)/g, “”);
}
String.prototype.RTrim = function()
{
return this.replace(/(\s*$)/g, “”);
}
//–>
</SCRIPT>
<input type=”text” value= 前后都是空格 id=”space”>
<input type=”button” value=”去前后空格” οnclick=”javascript:document.getElementById(‘space’).value=document.getElementById(‘space’).value.Trim();document.getElementById(‘space’).select();”>
<input type=”button” value=”去前空格” οnclick=”javascript:document.getElementById(‘space’).value=document.getElementById(‘space’).value.LTrim();document.getElementById(‘space’).select();”>
<input type=”button” value=”去后空格” οnclick=”javascript:document.getElementById(‘space’).value=document.getElementById(‘space’).value.RTrim();document.getElementById(‘space’).select();”>
<input type=”button” value=”还原” οnclick=”javascript:document.getElementById(‘space’).value= 前后都是空格 ‘;”>去除所有空格:
str = str.replace(/\s+/g,”");
去除两头空格:
str = str.replace(/^\s+|\s+$/g,”"); php程序员站去除空格(TimeSheet用过)

arg0=arg0.replace(/\s+$|^\s+/g,”");