javascript_0707作业

作业内容：1. 变量,常量,数据类型,实例演示,注意命名规范;

  //变量
             let n1 = 100;
             console.log(typeof n1);
             let n2 = "123";
             console.log(typeof n2);
             let n3 = true;
             console.log(typeof n3);
             let n4 = undefined;
             console.log(typeof n4);
             let n5 = null;
             console.log(typeof n5);
             //常量
             const NATION = "china";
             //对象
             const person = {
                 name:'zhangsan',
                 gender:'male',
                 job:'work'
             };
             console.log(person);
             //数组
             const colors =["red","green","blue"];
             console.log(colors);

2. 函数参数与返回值,匿名函数及箭头函数的转化,实例演示;

 //函数参数与返回值
             function sum (a,b){
                 return a+b;
             }
             console.log(sum(30,40));
             //匿名函数与箭头函数的转化
             let sum1 = function(a,b){
                 return a+b;
             }
             sum1 = (a,b)=>{
                 return a+b;
             }
             //只有一条语句时
             sum1 =(a,b)=>a+b;