前端学习案例-关于new object的困惑

new object的obj对象得到啥

<!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>object</title>
</head>
<body>
    <script>
        var obj={}
        obj.a=1;
        var newObj=new Object(obj)
        console.log(newObj===obj)//true
        //引用值 ->object.prototype
    </script>
</body>
</html>

new object的数组得到啥

<!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>object</title>
</head>
<body>
    <script>
        // var obj={}
        // obj.a=1;
        // var newObj=new Object(obj)
        // console.log(newObj===obj)//true
        //引用值 ->object.prototype

        var arr=[1,2,3,4]
        var newArr=new Object(arr)
        console.log(newObj===obj)//true

    </script>
</body>
</html>

new arr+数组

<!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>object</title>
</head>
<body>
    <script>
        // var obj={}
        // obj.a=1;
        // var newObj=new Object(obj)
        // console.log(newObj===obj)//true
        //引用值 ->object.prototype

        var arr=[1,2,3,4]
        var newArr=new Array(arr)
        console.log(newObj===obj)//false

    </script>
</body>
</html>

原始值不能添加属性

<!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>object</title>
</head>
<body>
    <script>
        // var obj={}
        // obj.a=1;
        // var newObj=new Object(obj)
        // console.log(newObj===obj)//true
        //引用值 ->object.prototype

        // var arr=[1,2,3,4]
        // var newArr=new Array(arr)
        // console.log(newObj===obj)//false


        //基本值
        var a=1
        a.b=2;
        console.log(a.b)


    </script>
</body>
</html>

posted @ 2022-08-20 21:55  前端导师歌谣  阅读(21)  评论(0)    收藏  举报