JavaScript数组与对象解构详解：完全、部分、默认值及失败处理

//1.完全解构  变量个数与数据个数一致
        let [a, b, c] = arr;
         let [a1, a2] = ["hello", "wolrd"]
        console.log(a1, a2);

        //2.不完全解构(变量个数小于数据个数)
         let [a, b] = [10, 20, 30, 40]
         console.log(a,b);

  //3.解构失败 (变量个数大于数据个数)
        let [a, b, c] = [10, 100]
        console.log(a,b,c)

  //默认值 (取不到值的时候，默认值生效)
         let [a = 0, b = 0, c = 0, d = 0] = [10, 20, 30]
         console.log(a + b + c + d);
         console.log(a, b, c, d);
         let [a = 0, b = 0, c = 0, d = undefined] = [1, 2, undefined]
         console.log(a, b, c, d);

//4.解构缺省
         let [, , , a, , b] = [10, 20, 'true', '(*^▽^*)', 200, '难过(ಥ﹏ಥ)'];
         console.log(a);
         console.log(b);
        //其它情况
         let [, , , a] = [10, 20, ['hello', 'world'], ['小红']]
         let [a1] = a;
         let [, , , [a]] = [10, 20, ['hello', 'world'], ['小红']]
         let [[[[a]]]] = [[[[10]], ['哈哈哈']], 100, 200];//

   //1.完全解构
         let { name: sName, age: sAge, attr: att } = obj;
         console.log(sName, sAge, att);

//2.不完全解构
         let {name:sName}=obj;
         console.log(sName);

 //3.解构失败
         let { no: id, name: sName } = obj;
         console.log(id, sName);
         console.log('hello');
         console.log('world');
         console.log('哈哈哈');

 //4.解构默认值
        let {
            name: sName = "张三",
            age: sAge = 0,
            no:id='10001'
        } = obj;
        console.log(sName,sAge);
        console.log(id);

 let rst = {
            code: 200,
            msg: "用户信息",
            data: [
                { id: 1, title: "测试账号", token: "lsajfdlasfjdaslfdjasfd89dfa7sf9dasdfasdf" }
            ]
        }
        let { code, data = [] } = rst;