Javascript mobx存储中未定义数组长度
我试图从Redux转换到Mobx,并尝试在Mobx存储中设置一个数组,我使用decorators来设置值。我可以从存储返回静态值,但是下面的数组长度总是抛出未定义的值。 不确定下面的代码有什么问题。有什么建议吗Javascript mobx存储中未定义数组长度,javascript,arrays,reactjs,mobx,mobx-react,Javascript,Arrays,Reactjs,Mobx,Mobx React,我试图从Redux转换到Mobx,并尝试在Mobx存储中设置一个数组,我使用decorators来设置值。我可以从存储返回静态值,但是下面的数组长度总是抛出未定义的值。 不确定下面的代码有什么问题。有什么建议吗 import {observable, action, computed} from 'mobx'; class FormDataStore { @observable formdata = [1,2,3]; @action updateFormData = (fo
import {observable, action, computed} from 'mobx';
class FormDataStore {
@observable formdata = [1,2,3];
@action updateFormData = (formdata) => {
this.formdata.push(formdata);
}
@computed get readdata() {
return this.formdata.length;
}
}
const store = new FormDataStore();
export default store
错误
FormDataStore.js:12 Uncaught TypeError: Cannot read property 'length' of undefined
at FormDataStore.get (FormDataStore.js:12)
at trackDerivedFunction$$1 (mobx.module.js:1142)
at ComputedValue$$1.computeValue (mobx.module.js:934)
at ComputedValue$$1.trackAndCompute (mobx.module.js:919)
at ComputedValue$$1.get (mobx.module.js:879)
at ObservableObjectAdministration$$1.read (mobx.module.js:3822)
at FormDataStore.get (mobx.module.js:4086)
at FormDataStore.get (mobx.module.js:295)
at PreviewWindow.render (PreviewWindow.js:24)
at Object.allowStateChanges$$1 (mobx.module.js:653)
下面是我如何尝试读取数据
import React from "react";
import { Container } from "semantic-ui-react";
import Highlight from "react-highlight";
import {inject,observer} from 'mobx-react';
@inject('FormDataStore')
@observer
class PreviewWindow extends React.Component {
render() {
const {FormDataStore} = this.props;
console.log(FormDataStore)
return (
<Container>
<h1>JSon Preview</h1>
<h1>{FormDataStore.getFormData}</h1>
<Highlight language="javascript">{FormDataStore.readdata}</Highlight>
</Container>
);
}
}
export default PreviewWindow;
从“React”导入React;
从“语义ui反应”导入{Container};
从“反应高光”导入高光;
从“mobx react”导入{inject,observer};
@注入('FormDataStore')
@观察者
类PreviewWindow扩展了React.Component{
render(){
const{FormDataStore}=this.props;
console.log(FormDataStore)
返回(
JSon预览
{FormDataStore.getFormData}
{FormDataStore.readdata}
);
}
}
导出默认预览窗口;
在中插件的顺序很重要。babelrc
必须更改babel配置中插件的顺序才能解决问题
/// WRONG
"plugins": [
"transform-class-properties",
"transform-decorators-legacy"
]
// RIGHT
"plugins": [
"transform-decorators-legacy",
"transform-class-properties"
]
你能告诉我你是如何访问readdata的吗?@kemicofa我用readdata部分更新了这篇文章。谢谢