chuck
/
es6-11study


			
				
					
						
						
							123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263
							<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>箭头函数</title>
</head>
<body>
    <script>
        let fn = function(){

        }

        let fn = (a,b) =>{
            return a+b;
        }
        //调用
        let r = fn(3,4)
        console.log(r)

        //this是静态的，始终指向函数声明时所在的作用域下的this值
            function getName(){
                console.log(this.name)
            }
            let getName2 = () =>{
                console.log(this.name)
            }
            window.name = 'zhangsan'
            const school = {
                name = 'lisi'
            }
            getName()  //zhangsan
            getName2()  //zhangsan

            //call
            getName.call(school) //lisi
            getName2.call(school)  //zhangsan   保持不变
        //不能作为构造函数实例化对象
            let Person = (name,age) =>{
                this.name = name;
                this.age = age;
            }
            let me = new Person('zhang',18)
            console.log(me)   //报错
        
        //不能使用arguments变量
        let fn = () =>{
            console.log(arguments)  // not defined
        }
        fn()

        //简写 
            //省略小括号 当形参有且只有一个时
            let add = n =>{
                return n*n
            }
            //省略花括号 当代码只有一条语句时,return也必须省略
            let pow = (n) => n*n
            
    </script>
</body>
</html>