Question

我正在使用React-Router和Alt在this tutorial之后在ES6中构建一个React Web应用程序。我的所有组件都正确呈现，但是在刷新浏览器页面时，那些具有构造函数的组件会中断。这是错误。

TypeError: undefined is not a function
   at new Track (/Users/juancarlosfarah/Git/maestro/src/components/Track.js:14:17)
   at [object Object].ReactCompositeComponentMixin.mountComponent (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactCompositeComponent.js:135:16)
   at [object Object].wrapper [as mountComponent] (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactPerf.js:70:21)
   at Object.ReactReconciler.mountComponent (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactReconciler.js:38:35)
   at [object Object].ReactCompositeComponentMixin.mountComponent (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactCompositeComponent.js:247:34)
   at [object Object].wrapper [as mountComponent] (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactPerf.js:70:21)
   at Object.ReactReconciler.mountComponent (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactReconciler.js:38:35)
   at [object Object].ReactCompositeComponentMixin.mountComponent (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactCompositeComponent.js:247:34)
   at [object Object].wrapper [as mountComponent] (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactPerf.js:70:21)
   at Object.ReactReconciler.mountComponent (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactReconciler.js:38:35)
   at ReactDOMComponent.ReactMultiChild.Mixin.mountChildren (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactMultiChild.js:192:44)
   at ReactDOMComponent.Mixin._createContentMarkup (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactDOMComponent.js:289:32)
   at ReactDOMComponent.Mixin.mountComponent (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactDOMComponent.js:199:12)
   at Object.ReactReconciler.mountComponent (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactReconciler.js:38:35)
   at [object Object].ReactCompositeComponentMixin.mountComponent (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactCompositeComponent.js:247:34)
   at [object Object].wrapper [as mountComponent] (/Users/juancarlosfarah/Git/maestro/node_modules/react/lib/ReactPerf.js:70:21)

在Track.js的第14行，定义了构造函数：

class Track extends React.Component {

    constructor(props) {
        super(props);
        console.debug("Constructing Track...");
        this.state = TrackStore.getState();
        this.handleTextChange = this.handleTextChange.bind(this);
        this.handleSaveClick = this.handleSaveClick.bind(this);
        this.handleUndoClick = this.handleUndoClick.bind(this);
        this.renderButtons = this.renderButtons.bind(this);
        this.onChange = this.onChange.bind(this);
    }
    ...
}

在app.js中，我按如下方式渲染路线：

Router.run(routes, Router.HistoryLocation, function(Handler) {
    React.render(<Handler />, document.getElementById('app'));
});

它们在routes.js中定义：

export default (
    <Route handler={App}>
        <Route path='/' handler={Home} />
        <Route path="/tracks/" handler={Tracks} />
        <Route path="/track/:id" handler={Track} />
    </Route>
);

在server.js中，使用Swig渲染页面。

app.use(function(req, res) {
    Router.run(routes, req.path, function(Handler) {
        let html = React.renderToString(React.createElement(Handler));
        let page = swig.renderFile('views/index.html', { html: html });
        res.send(page);
    });
});

即使我删除constructor中的所有代码并只留下console.log语句，我刷新浏览器时也会收到错误。如果没有构造函数，则刷新时页面呈现正常。

Answer 1

经过很长一段时间，我想出了我遇到的问题。在Track.js中我添加了一行来帮助我调试错误，它调用console.debug()（我现在已经明确地将其添加到问题中的代码中，但我最初没有显示它）。当客户端呈现Track.js时，这不是问题，因为Chrome中的控制台可以运行console.debug()。但是，当直接访问URL时，页面将由服务器呈现，该服务器不支持console.debug()。因此，应用程序将破坏并显示出神秘的错误。删除该行或将其更改为console.log()可解决此问题。

使用ES6构造函数呈现应用程序渲染React组件的刷新页面

1 个答案: