Question

我已经修改了MERN堆栈http://mern.io/，以支持DApp。我正在尝试按以下方式删除应用程序中的页面。

HomePage.js

 const HomePage = () => (
  <div>
    <div>
      <h1>Home Page</h1>
      <p>
        This is the home page for our limitless application.
        Let's tell the users here what we are about and explain
        how the application works...briefly. This would also be
        a good place to check and make sure that metamask is installed,
        and to let them know that they will need it.
      </p>
    </div>
    <Home />
  </div>
);

export { HomePage };

我收到以下错误 TypeError：无法读取未定义的属性“需要” 在/usr/src/app/server/util/fetchData.js:9:21 该问题似乎是堆栈附带的以下代码的一部分。

https://github.com/caljrimmer/isomorphic-redux-app/blob/73e6e7d43ccd41e2eb557a70be79cebc494ee54b/src/common/api/fetchComponentDataBeforeRender.js

fetchData.js

/*
Utility function to fetch required data for component to render in server side.
This was inspired from https://github.com/caljrimmer/isomorphic-redux-app/blob/73e6e7d43ccd41e2eb557a70be79cebc494ee54b/src/common/api/fetchComponentDataBeforeRender.js
*/
import { sequence } from './promiseUtils';

export function fetchComponentData(store, components, params) {
  const needs = components.reduce((prev, current) => {
    return (current.need || [])
      .concat((current.WrappedComponent && (current.WrappedComponent.need !== current.need) ? current.WrappedComponent.need : []) || [])
      .concat(prev);
  }, []);

  return sequence(needs, need => store.dispatch(need(params, store.getState())));
}

promiseUtils.js

/**
 * Throw an array to it and a function which can generate promises
 * and it will call them sequentially, one after another
 */
export function sequence(items, consumer) {
  const results = [];
  const runner = () => {
    const item = items.shift();
    if (item) {
      return consumer(item)
        .then((result) => {
          results.push(result);
        })
        .then(runner);
    }

    return Promise.resolve(results);
  };

  return runner();
}

有人可以帮助我了解这里的问题以及其他代码到底试图做什么吗？我仍在学习反应，所以请保持温柔

MERN启动器堆栈。无法读取未定义的属性需求

0 个答案: