javascript去除字串前后的空格

  /** 去除字串前后的空格  */  function trim(s) {    var count = s.length;    var st    = 0;       // start    var end   = count-1; // end      if (s == "") return s;    while (st < count) {      if (s.charAt(st) == " ")        st ++;      else        break;    }    while (end > st) {      if (s.charAt(end) == " ")        end --;      else        break;    }    return s.substring(st,end + 1);  } 

抄自：http://blog.csdn.net/lutinghuan/article/details/8275800