实例演示函数参数与返回值、演示模板字面量与模板函数

    <script>
        // 1.实例演示函数参数与返回值
        // 1.参数不足：默认参数
        let add = (a,b) => {
            return a+b;
        }
        console.log(add(1,2));
        console.log(add(100));
        console.log("-----------------------------------------");
        let addN = (a,b=0) => {
            return a+b;
        }
        console.log(addN(1,2));
        console.log(addN(100));
        console.log("-----------------------------------------");
        // 2.参数过多(剩余参数) 
        // ...rest:用在函数的形参中，归并
        // ...用在参数调用的实参中，是解包，打散
        let addRange = (...arr) => {
            let out = 0;
            for(let i=0;i<arr.length;i++){
                out += arr[i];
            }
            return out;
        }
        console.log(addRange(1,2,3,4,5,6,7,8,9,10));
        let addlist = [1,2,3,4,5,6,7,8,9,10];
        console.log(addRange(...addlist));
        // 返回值为一个值
        let say = ()=>"Hello php.cn";
        console.log(say());
        // 返回多个值
        let rangeOut = ()=>[1,2,3,4,5,6,7,8,9,10];
        console.log(rangeOut());
        let girlFriend = ()=>({
            name: "姑奶奶",
            age:18,
            gender:"female",
            habbit:"buy buy buy",
            getInfo(){
                return `${this.age}岁的${this.name}，最大的爱好是${this.habbit}. :<`;
            }
        })
        console.log(girlFriend());
        console.log(girlFriend().getInfo());
        //2.实例演示模板字面量与模板函数
        let studentName = "Dave" ;
        //模板字面量
        let demo = `Hello ${studentName}`
        console.log(demo);
        //模板函数
        alert `Hello Dave`;
    </script>