js - 常用功能方法汇总（updating...）

 1 /*
 2     * @Author: guojufeng@ 
 3     * @Date: 2017-12-20 15:07:06
 4     * @purpose 获取一个值的类型
 5     * @param {variateName} target: 要获取类型的变量名或对象
 6     * @output {string} result || "null": 返回的参数 - result或者null,为字符串形式的
 7     */
 8     function getType(target) {
 9       if(target === null){
10         console.log(target)
11         return "null";
12       }
13       let result = typeof (target);
14       if (result == "object") { 
15         if (target instanceof Array) {
16           result = "array";
17         } else if (target instanceof Object) {
18           result = "object";
19         }
20       }
21       console.log(result)
22       return result;//返回类型值的字符串形式
23     }

1 var nu= null;// null 怎么算
2 var un= undefined;
3 var c = new Array;
4 var d = {};
5 console.log(getType(c),getType(d),getType(nu),getType(un))