es6基础(2)--解构赋值

 //解构赋值

 {
     let a,b,rest;
     [a,b]=[1,2];
     console.log(a,b);
 }
 //数组解构赋值
 {
     let a,b,rest;
     [a,b,...rest]=[1,2,3,4,5,6];
     console.log(a,b,rest);
 }
 //对象解构赋值
 {
     let a,b;
     ({a,b}={a:1,b:2})
     console.log(a,b);
 }

 {
     let a,b,c,rest;
     [a,b,c=3]=[1,2];
     console.log(a,b,c);
 }
 //变量交换
 {
     let a=1;
     let b=2;
     [a,b]=[b,a];
     console.log(a,b);
 }

 {
     function f(){
         return [1,2]
     }
     let a,b;
     [a,b]=f();
     console.log(a,b)
 }
 {
     function f(){
         return [1,2,3,4,5,6];
     }
     let a,b,c;
     [a,,,b]=f();
     console.log(a,b);
 }
 //当只要数组内的某几个的时候
 {
     function f(){
         return [1,2,3,4,5,6];
     }
     let a,b,c;
     [a,...b]=f();
     console.log(a,b);
 }
 //对象的赋值
 {
     let o={p:42,q:true};
     let {p,q}=o;
     console.log(p,q);
 }
 {
     let {a=10,b=5}={a:3};
     console.log(a,b);
 }
 {
     let metaData={
         title:'abc',
         test:[{
             title:'test',
             desc:'description'
         }]
     }
     let {title:esTitle,test:[{title:cntitle}]}=metaData;
     console.log(esTitle,cntitle);
 }