es8(string,object)字符串填充：让str="abc";让a=str.padEnd(5);让b=str.padStart(5);让c=str.padEnd(5,"a");让d=str.padStart(5,"a");console.log("|"+str+"|");//打印出|abc|console.log("|"+a+"|");//打印出|abc|console.log("|"+b+"|");//打印出来|美国广播公司|console.log("|"+c+"|");//打印出|abcaa|console.log("|"+d+"|");//打印出|aaabc|object:letobj={name:"大胖子",age:23};让arr=["a","b"];console.log(Object.values(obj));//打印出["bigfat",23]console.log(Object.values(arr));//打印出["a","b"]console.log(Object.entries(obj));//打印出[Array(2),Array(2)]函数对象的定义调用时可以在参数后面加一个逗号：functionfn(a,b){安慰。日志（123）；}fn(1,2,);
