使用变量动态访问对象属性

2022-08-29 22:15:01

我正在尝试使用动态名称访问对象的属性。这可能吗?

const something = { bar: "Foobar!" };
const foo = 'bar';
something.foo; // The idea is to access something.bar, getting "Foobar!"

答案 1

两种方法可以访问对象的属性

  • 点表示法:something.bar
  • 括号表示法:something['bar']

方括号之间的值可以是任何表达式。因此,如果属性名称存储在变量中,则必须使用括号表示法:

var something = {
  bar: 'foo'
};
var foo = 'bar';

// both x = something[foo] and something[foo] = x work as expected
console.log(something[foo]);
console.log(something.bar)

答案 2

这是我的解决方案:

function resolve(path, obj) {
    return path.split('.').reduce(function(prev, curr) {
        return prev ? prev[curr] : null
    }, obj || self)
}

使用示例:

resolve("document.body.style.width")
// or
resolve("style.width", document.body)
// or even use array indexes
// (someObject has been defined in the question)
resolve("part.0.size", someObject) 
// returns null when intermediate properties are not defined:
resolve('properties.that.do.not.exist', {hello:'world'})