⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙

JS之形参带默认值的写法代码

JS之形参带默认值的写法代码

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>JS之形参带默认值的写法代码</title>
</head>
<body>
<script>
    function c(x, y){
        //console.log(y);   //结果：undefined或者值
        if(y == undefined){
            y = 3; //如果调用函数时，没有传递第二个参数y的值，那么让y=3
        }
        console.log(x + y); //结果：5 6
    }
    c(2);
    c(2, 4);
</script>
</body>
</html>
posted @ 2018-10-14 09:57  羊驼可以吃吗  阅读(348)  评论(0)  编辑  收藏  举报
⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙ ⊙︿⊙