我正在尝试这样做:
if (typeof window !== `undefined`) {
import Keyboard from "react-simple-keyboard"
import "react-simple-keyboard/build/css/index.css"
}
但我有
'import' and 'export' may only appear at the top level (12:2)
对此我能做些什么吗?只有当我们在浏览器中时,我才需要加载我的键盘。在生成过程中没有。
组件应该使用React.lazy
,而require()
。
React.lazy
函数允许您将动态导入渲染为常规组件。
if (typeof window !== `undefined`) {
import Keyboard from "react-simple-keyboard"
import "react-simple-keyboard/build/css/index.css"
}
// Becomes
if (typeof window !== `undefined`) {
// Component
const Keyboard = React.lazy(() => import('react-simple-keyboard'));
// Resolve
require('react-simple-keyboard/build/css/index.css');
}
- 查看导入与需要
- 此外,您应该检查
import()
您可以使用动态导入语法
const Keyboard=导入("实际键盘"(
参考:https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import#Dynamic_Imports
Gatsby支持开箱即用的动态导入。
useEffect(() => {
async function dynamicImportModule() {
const dynamicModule = (await import('some-module'))
// perform remaining tasks with dynamicModule
}
dynamicImportModule()
}, [someDependency])