javascript 如何将对象解构为已定义的变量？
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How to destructure an object to an already defined variable?
提问by Gajus
The following produces a syntax error:
以下会产生语法错误：
let source,
screenings,
size;
source = {
screenings: 'a',
size: 'b'
};
{
screenings,
size
} = source;
Expected result:
预期结果：
screenings should be equal to 'a'
size should be equal to 'b'
回答by CodingIntrigue
You need to use assignment without declarationsyntax:
({
screenings,
size
} = source);
From the linked docs:
从链接的文档：
The ( .. ) around the assignment statement is required syntax when using object literal destructuring assignment without a declaration
在没有声明的情况下使用对象字面量解构赋值时，赋值语句周围的 ( .. ) 是必需的语法
And obviously you need to use this as you can't redeclare a letvariable. If you were using var, you could just redeclare var { screenings, size } = source;
显然你需要使用它，因为你不能重新声明一个let变量。如果您正在使用var，则可以重新声明var { screenings, size } = source;
