function ltrim(tstr)
{
    var ret=tstr;
    
    if(ret.length > 0)
    {
        while(ret.charAt(0) == ' ')
        {
            if(ret.length==1) return("");
            ret=ret.substring(1,ret.length);
        }
    }
    return(ret);
}

function rtrim(tstr)
{
    var ret=tstr;
    
    if(ret.length > 0)
    {
        while(ret.charAt(ret.length-1) == ' ')
        {
            if(ret.length==1) return("");
            ret=ret.substring(0,ret.length-1);
        }
    }
    return(ret);
}

function trim(tstr)
{
    var ret=ltrim(tstr);
    ret=rtrim(ret);
    return(ret);
}