function test(){
	var tt =" hoocy  is very good  boy";
	tt.Trim();
	alert(tt);
	
}
//去除字符串中间空格
String.prototype.Trim = function() { 
   return this.replace(/(^\s*)|(\s*$)/g, ""); 
}
//去除字符串左侧空格
String.prototype.LTrim = function() { 
   return this.replace(/(^\s*)/g, ""); 
}
//去除字符串右侧空格
String.prototype.RTrim = function() { 
   return this.replace(/(\s*$)/g, ""); 
}


function  jtrim(s)  
{  
   var  i,b=0,e=s.length;  
    for(i=0;i<s.length;i++) //去左空格
          if(s.charAt(i)!=' '){b=i;break;}  
     if(i==s.length)  
        return  "";  

   for(i=s.length-1;i>b;i--) // 去右空格
       if(s.charAt(i)!=' '){e=i;break;}  
       
  	return  s.substring(b,e+1);  
}
function Jtrim(str)
{
        var i = 0;
        var len = str.length;
        if ( str == "" ) return( str );
        j = len -1;
        flagbegin = true;
        flagend = true;
        while (( flagbegin == true) && (i< len))
        {
           if ( str.charAt(i) == " " )
                {
                  i=i+1;
                  flagbegin=true;
                }
                else
                {
                        flagbegin=false;
                }
        }

        while  ((flagend== true) && (j>=0))
        {
            if (str.charAt(j)==" ")
                {
                        j=j-1;
                        flagend=true;
                }
                else
                {
                        flagend=false;
                }
        }

        if ( i > j ) return ("");

        trimstr = str.substring(i,j+1);
        return trimstr;
}



function IgnoreSpaces(Str){
    var ResultStr = "";
    Temp=Str.split(" "); //双引号之间是个空格；
    for(i = 0; i < Temp.length; i++)
    	ResultStr +=Temp[i];
    return ResultStr;
} 

?……

非正则判断输入是否数字

?

function checkNum(num)
{
	var stringNum = "0123456789";
    if("" === num || 0 === num.length)
    {
        return 1;
    }
    for(var i=0;i<num.length;i++)
    {
        if( -1 === stringNum.indexOf( num.charAt(i) ) )
        {
            return 1;
        }
    }
    return 0;
}