(這些例子已經在node.js 6.9.x下,運行通過)js中循環語句有forEach，for in，for of 三種了一般的遍歷數組的方法:- var array = [1,2,3,4,5,6,7];
- for (var i = 0; i < array.length; i) {
- console.log(i,array[i]);
- }
- for(let index in array) {
- console.log(index,array[index]);
- };
- array.forEach(v=>{
- console.log(v);
- });
- array.forEach(function(v) {
- console.log(v);
- });
- var A = {a:1,b:2,c:3,d:"hello world"};
- for(let k in A) {
- console.log(k,A[k]);
- }
- for(let v of array) {
- console.log(v);
- };
- let s = "helloabc";
- for(let c of s) {
- console.log(c);
- }
- for(let index in s) {
- console.log(index,s[index]);
- }
- var set = new Set();
- set.add("a").add("b").add("d").add("c");
- var map = new Map();
- map.set("a",1).set("b",2).set(999,3);
- for (let v of set) {
- console.log(v);
- }
- console.log("--------------------");
- for(let [k,v] of map) {
- console.log(k,v);
- }
|