正在访问数组解构中的特定元素？

Question

const { navigation, currentScreen, childIndex } = this.state
const screen = navigation[currentScreen]

如何在同一行中编写这两行代码？

Answer 1

使用{ [currentScreen]: screen }，请确保您事先提取了currentScreen：

const state = { navigation: { foo: 'val' }, currentScreen: 'foo' };

const { navigation, currentScreen, childIndex, navigation: { [currentScreen]: screen } } = state
console.log(screen);