数据交互集合~

1、数组对象id提取

let array=[{
    id:1,
    name:"李白",
},{
    id:2,
    name:"杜甫",
},{
    id:3,
    name:"白居易",
}];

let arrayId = array.map(a => a.id);
console.log(arrayId); //[1, 2, 3]

2、根据数组id获取对象

let array=[{
    id:1,
    name:"李白",
},{
    id:2,
    name:"杜甫",
},{
    id:3,
    name:"白居易",
}];

//根据数组id获取对象
let item = array.find((item) => {
    return item.id == 2
});
console.log(item); //{id: 2, name: '杜甫'}

3、数组对象中添加值

let array=[{
    id:1,
    name:"李白",
},{
    id:2,
    name:"杜甫",
},{
    id:3,
    name:"白居易",
}];

array.map(a => {
    a['sex']='男';
});
console.log(array); //[{id: 1, name: "李白", sex: "男"},{id: 2, name: '杜甫', sex: '男'},{id: 3, name: '白居易', sex: '男'}]

4、数组对象中删除值

let array=[{
    id: 1,
    name: '李白',
    sex: '男'
},{
    id: 2,
    name: '杜甫',
    sex: '男'
},{
    id: 3,
    name: '白居易',
    sex: '男'
}];

array.map(a => {
    delete a.sex;
});
console.log(array); //[{id: 1, name: "李白"},{id: 2, name: '杜甫'},{id: 3, name: '白居易'}]

5、数组追加对象

let array=[{
    id: 1,
    name: '李白',
    sex: '男'
},{
    id: 2,
    name: '杜甫',
    sex: '男'
},{
    id: 3,
    name: '白居易',
    sex: '男'
}];

let item = {id:4, name:'A星', sex:'男'};
array.push(item);
console.log(array); //[{id: 1, name: "李白"},{id: 2, name: '杜甫'},{id: 3, name: '白居易'},{id: 4, name: 'A星',sex: '男'}]

6、根据id替换数组对象中的数据

let array=[{
    id: 1,
    name: '李白',
    sex: '男'
},{
    id: 2,
    name: '杜甫',
    sex: '男'
}];

let obj = {id:2, name:'A星', sex:'男'};
arr = array.map(item => item.id === obj.id ? obj : item);
console.log(arr); //[{id: 1, name: '李白', sex: '男'},{id: 2, name: 'A星', sex: '男'}]

7、合并两个数组的三种方法

//方法一：concat
var a = [1,2,3];
var b = [4,5,6];
var c1 = a.concat(b);
console.log(c1); //[1,2,3,4,5,6];

//方法二：for循环
var a = [1,2,3];
var b = [4,5,6];
for( var i in b)
{
    a.push(b[i]);
}
console.log(a); //[1,2,3,4,5,6];

//方法三：apply
var a = [1,2,3];
var b = [4,5,6];
a.push.apply(a,b);
console.log(a); //[1,2,3,4,5,6];