调用对象时使用对象的成员而不是对象本身

Question

这是类和对象：

class BDImage
{
    constructor(path)
    {
        this.img = new Image();
        this.img.src = path;
    }
}

var myImage = new BDImage("path/to/image.png");

我想访问/使用myImage的{​​{1}}成员，而不必一直输入img。相反，只是myImage.img，然后我实际上是指myImage。

如何？

Answer 1

只需将引用缓存在变量中：

class BDImage
{
    constructor(path)
    {
        this.img = new Image();
        this.img.src = path;
    }
}

var myImage = new BDImage("path/to/image.png");

var imgProp = myImage.img;  // Now imgProp points to myImage.img

console.log(imgProp.src);

Answer 2

您似乎需要一些功能编程！

var textFields = <Widget>[];

希望有帮助！

Answer 3

扩展;）

mysql> SELECT
    QUARTER ('2019-01-01') AS `1th q`,
    QUARTER ('2019-04-30') AS `1th q`,
    QUARTER ('2019-05-01') AS `2th q`,
    QUARTER ('2019-08-31') AS `2th q`,
    QUARTER ('2019-09-01') AS `3th q`,
    QUARTER ('2019-12-31') AS `3th q`;
+-------+-------+-------+-------+-------+-------+
| 1th q | 1th q | 2th q | 2th q | 3th q | 3th q |
+-------+-------+-------+-------+-------+-------+
|     1 |     2 |     2 |     3 |     3 |     4 |
+-------+-------+-------+-------+-------+-------+
1 row in set

mysql> 

Object.defineProperty

+-------+-------+-------+-------+-------+-------+
| 1th q | 1th q | 2th q | 2th q | 3th q | 3th q |
+-------+-------+-------+-------+-------+-------+
|     1 |     1 |     2 |     2 |     3 |     3 |
+-------+-------+-------+-------+-------+-------+