text: // 数据类型判断
  function _typeof(obj){
    var s = Object.prototype.toString.call(obj);
  
    return s.match(/\[object (.*?)\]/)[1].toLowerCase();
  };
  
  
  _typeof([12,3,343]);
  "array"
  
  _typeof({name: 'zxc', age: 18});
  "object"
  
  _typeof(1);
  "number"
  
  _typeof("1");
  "string"
  
   _typeof(null);
  "null"
  
  _typeof(undefined);
  "undefined"
  
  _typeof(NaN);
  "number"
  
  _typeof(Date);
  "function"
  
  _typeof(new Date());
  "date"
  
  _typeof(new RegExp());
  "regexp"