1.js 往本地内存中写数据

localStorage.setItem('key', 'value'); // 使用localStorage存储数据

sessionStorage.setItem('key', 'value');// 使用sessionStorage存储数据

let value = localStorage.getItem('key'); // 读取localStorage数据

let value = sessionStorage.getItem('key'); // 读取sessionStorage数据

localStorage.removeItem('key'); // 删除localStorage数据

sessionStorage.removeItem('key'); // 删除sessionStorage数据

localStorage.clear(); // 清空所有localStorage数据

sessionStorage.clear(); // 清空所有sessionStorage数据

2. js 中调试debugger

3.js 中prototype

student.prototype.add = function (a,b) {return a + b;
}

3.js 中的foreach var arr = [1,2,3,4,5,6];

arr.forEach(item=> console.log(item));

for( index in arr){

console.log(arr[index]);

}

4.js 中的集合

const map = new Map(); map.set("name","zhangsan");

console.log(map.get("name"));

var set = new Set();
set.add(1);
set.add(1);
console.log(set);

4. 面向对象

class Persion {constructor(name,age) {this.name = name;this.age = age;}showName(){return this.name;}setName(name){this.name = name;}
}class student extends  Persion {constructor(name,age,sex) {super(name,age);this.sex = sex;}
}
var p = new Persion("zhangsan",20);
console.log(p.showName());
p.setName("wangwu");
console.log(p.showName());
var s = new student("zhangsan",20,1);
console.log(s.name);
console.log(s.sex);

5. js promise

var p1 = new Promise(resolve => {console.log("p1")
},reject => {console.log("error");
});
var p2 = new Promise(resolve => {console.log("p1")
},reject => {console.log("error");
})
var p3 = new Promise(resolve => {console.log("p1")
},reject => {console.log("error");
})
Promise.all([p1,p2,p3]).then(result =>{console.log("result");
}).catch(error => {console.log("Error");
})

6. export default {

}