使用解构为已定义的变量赋值

Question

根据 javascript.info，下面的代码应该可以工作， https://javascript.info/destructuring-assignment#object-destructuring

在我的项目中，我已经定义了一些变量，现在我尝试使用 destructuring 来赋值但是，我无法运行下面的代码。

// This also does not work.
let title, width, height;
myobj = {title: "Menu", width: 200, height: 100}
({title, width, height}) = myobj;
console.log(title);

// This also does not work.
let title, width, height;
myobj = {title: "Menu", width: 200, height: 100}
{title, width, height} = myobj;
console.log(title);

Answer 1

您需要将整个表达式包裹在()中并在上一行添加一个分号

来自Assignment without declaration

The parentheses ( ... ) around the assignment statement are required when using object literal destructuring assignment without a declaration.

Your ( ... ) expression needs to be preceded by a semicolon or it may be used to execute a function on the previous line.

// This also does not work.
let title, width, height;
let myobj = { title: "Menu", width: 200, height: 100 }; // <- semicolon here
({ title, width, height } = myobj);
console.log(title);

使用解构为已定义的变量赋值

Using destructuring assign vaules to already defined varibales

javascript

object

destructuring