js中的 for, for in, for of foreach,filter使用

下面是对数组进行循环

   var array = [
        { id:
1, name: 'ohzri', birth: '1999.09.09', city: '湖北', salary: 9379 }, { id: 2, name: 'rqgfd', birth: '1999.10.28', city: '湖北', salary: 1060 }, { id: 3, name: 'fwfsh', birth: '1999.09.17', city: '广西', salary: 9736 }, { id: 4, name: 'bqibt', birth: '1999.04.20', city: '湖南', salary: 9471 }, { id: 5, name: 'ypklq', birth: '1999.06.28', city: '山东', salary: 3123 }, { id: 6, name: 'lupnr', birth: '2001.10.03', city: '河南', salary: 4630 }
      ];

 

使用:for

var arr1 = [];
for
(var i = 0; i < array.length; i++) { if (array[i].salary >= 3000 && array[i].salary <= 3500) { arr1.push(a[i]); } }

 

使用:for in  注意,for in 使用于循环对象,不建议对数组使用,因为输出的不是值,而是下标

var arr2 = [];
for
(let var1 in a) { if (var1.salary >= 3000 && var1.salary <= 3500) { arr2 = var1; } }

 

使用:for of

var arr3 = [];

for (let var2 of a) {
if (var2.salary >= 3000 && var2.salary <= 3500) {
                arr3.push(var2);
      }
 }
        

使用:Foreach

 

var arr4 = [];
a.forEach(function(i) {
if (i.salary >= 3000 && i.salary >= 3500) { arr4.push(i); } });

 

使用:filter

以下两句代码是等效:

var arrayfilter = a.filter(function(v){
return v.salary >= 3000 && v.salary >= 3500 });

var arrayFilter = a.filter((v) => v.salary >= 3000 && v.salary <= 3500);

 

可以输出看效果:

console.log(arr1);
console.log(arr2);
console.log(arr3);
console.log(arr4);
console.log(arrayFilter);

 

 

posted @ 2018-12-14 09:40  随★风  阅读(410)  评论(0编辑  收藏  举报