JavaScript常用代码

在这存一下JavaScript常用代码：

1.封装输出

1 var log = function() {
2     console.log.apply(console, arguments)
3 }
4 
5 // 测试:
6 log(123)
7 log("333", "666")
8 log("this ", "is", " a test!")

2.向JavaScript的字符串中添加一些功能

(1)添加reverse函数

1 String.prototype.reverse = function (){
2     return Array.prototype.reverse.apply(this.split('')).join('')
3 }
4 
5 // 测试:
6 console.log("wyb".reverse())
7 console.log("wyb666".reverse())

(2)添加字符串格式化函数format

 1 // JavaScript字符串格式化
 2     String.prototype.format = function (args) {
 3         var result = this;
 4         if (arguments.length > 0) {
 5             if (arguments.length == 1 && typeof (args) == "object") {
 6                 for (var key in args) {
 7                     if (args[key] != undefined) {
 8                         var reg = new RegExp("({" + key + "})", "g");
 9                         result = result.replace(reg, args[key]);
10                     }
11                 }
12             }
13             else {
14                 for (var i = 0; i < arguments.length; i++) {
15                     if (arguments[i] != undefined) {
16                         var reg = new RegExp("({)" + i + "(})", "g");
17                         result = result.replace(reg, arguments[i]);
18                     }
19                 }
20             }
21         }
22         return result;
23     };
24 
25 // 测试:
26 s = "{0} {1} {2}".format("this", "is a test", "for format")  // this is a test for format
27 console.log(s)