javascript实现类似java中getClass()得到对象类名的方

var getObjectClass = function (obj) {
 if (obj && obj.constructor && obj.constructor.toString()) {
   /
     for browsers which have name property in the constructor
     of the object,such as chrome 
    /
   if(obj.constructor.name) {
    return obj.constructor.name;
   }
   var str = obj.constructor.toString();
   /
     executed if the return of object.constructor.toString() is 
     "[object objectClass]"
    /
   if(str.charAt(0) == '[')
   {
     var arr = str.match(/\[\w+\s(\w+)\]/);
   } else {
     /
       executed if the return of object.constructor.toString() is 
       "function objectClass () {}"
       for IE Firefox
      /
     var arr = str.match(/function\s(\w+)/);
   }
   if (arr && arr.length == 2) {
      return arr[1];
   }
  }
  return undefined; 
};