feat(es6): 新增解构

Author: coderfocus

src/deconstruction.js

@@ -0,0 +1,68 @@
+//解构可以将对象的属性值绑定到任意数量的变量
+//解构可以用于对象、数组以及函数参数列表
+
+//++++++++++++++++++++++++++++++++++++++++++++
+//对象解构
+var people = {
+    name: 'song',
+    nickname: 'coderfocus',
+    metaData:{
+        age: 25,
+        gender: 'male'
+    }
+}
+var name = people.name
+
+//解构赋值
+var {name} = people
+console.log(name);
+
+//同时解构多个属性
+var {name,nickname} = people
+console.log(name + '-' + nickname);
+
+//解构别名
+var {name: lastname} = people
+console.log(lastname);
+
+//解构深度结构
+var {metaData: {age} } = people
+console.log(age);
+
+//解构不存在的属性返回 undefined
+var {boots} = people
+console.log(boots);
+
+// 解构嵌套属性的父对象是null或者undefined，抛出异常
+// var {boots: {size}} = people
+
+//默认值
+var {boots = {size:10}} = people
+console.log(boots);
+
+//嵌套属性默认值
+var {metaData: {size = 10}} = people
+console.log(size);
+
+//++++++++++++++++++++++++++++++++++++++++++++++++++
+//数组解构
+var coordinates = [12,-5]
+var [x,y] = coordinates
+console.log(x);
+console.log(y);
+
+//跳过不需要的值
+var names = ['song','wen','jie']
+var [firstname, ,lastname] = names
+console.log(lastname);
+
+//默认值
+var [firstname, , ,lastname = 'song'] = names
+console.log(lastname);
+
+//利用数组解构交换变量值
+var left = 5;
+var right = 7;
+[left,right] = [right,left]
+console.log(left);
+console.log(right);