Javascript 如何迭代从索引文件导入的多个模块
我有一个名为Javascript 如何迭代从索引文件导入的多个模块,javascript,es6-modules,Javascript,Es6 Modules,我有一个名为Polygons的目录,在那里我创建了一个index.js文件来从该目录导出所有文件。它看起来像这样: export {default as europe} from './europe' export {default as northAmerica} from './northAmerica' export default europe; import * as regions from './Polygons' europe文件导出变量如下: export {defaul
Polygons
的目录,在那里我创建了一个index.js
文件来从该目录导出所有文件。它看起来像这样:
export {default as europe} from './europe'
export {default as northAmerica} from './northAmerica'
export default europe;
import * as regions from './Polygons'
europe
文件导出变量如下:
export {default as europe} from './europe'
export {default as northAmerica} from './northAmerica'
export default europe;
import * as regions from './Polygons'
在我想使用这些变量的文件中,我像这样导入它们:
export {default as europe} from './europe'
export {default as northAmerica} from './northAmerica'
export default europe;
import * as regions from './Polygons'
我现在想以某种方式对这些导入进行迭代,有什么方法可以做到这一点吗
我尝试过:
for (const element of regions) {
console.log(element);
}
但是,我得到:
Uncaught (in promise) TypeError: Invalid attempt to iterate non-iterable instance.
In order to be iterable, non-array objects must have a [Symbol.iterator]() method.
它是一个对象,因此for..of将失败,但您可以使用
object.keys
或object.values
将其转换为数组,然后获得结果
下面是一个执行相同操作的示例代码:
keys=Object.keys(React)
for(键的常数键){
console.log(key,React[key])
}