1.变量值进行交换
        let a=10,b=20;
        console.log(a,b);
        [a,b]=[b,a];
        console.log(a,b);
2.数组解构
 // 等号左边是右边的模板,必须一样
        let [a,b,c] =[1,2,3];
        console.log(a,b,c);
可预设默认值
        [a,b,c='JS'] =[1,2];
        console.log(a,b,c);
可使用归并参数
        [a,b,...c] =[1,2,3,5,6,66];
        console.log(a,b,...c);
可省略部分参数
        [,,c] =[1,2,3,5,6,66];
        console.log(c);
3.对象解构
          ({id,name}={id:10,name:"手机"});
           console.log(id,name);
