我正在从API提取数据,然后将其映射为呈现到表中。但是,获取操作不起作用,并且在加载页面时状态保持不确定。尽管API可以正常工作并且可以正确发送数据,但是我在Postman和浏览器上都进行了检查。 如何解决这个问题?
页面崩溃了,我用Google搜索了一下,并添加了条件渲染以防止崩溃。但是仍然无法通过获取数据和映射来解决问题。
这是无法使用的页面的代码:
import React, { Component } from "react";
import fetch from "isomorphic-unfetch";
export default class extends Component {
static async getInitialProps() {
const res = await fetch("https://linktoapi/path");
const studentData = await res.json();
return studentData;
}
componentWillMount() {
this.setState({
studentData: this.props.studentData
});
}
render() {
return (
<table className="table is-striped is-fullwidth has-text-centered">
<thead>
<tr>
<th>Name</th>
<th>Class</th>
<th>Section</th>
<th>Batch</th>
<th>Contact No.</th>
</tr>
</thead>
<tbody>
{this.state.studentData && this.state.studentData.map(studentDataRow => (
<tr id={studentDataRow._id}>
<td>{studentDataRow.name}</td>
<td>{studentDataRow.class}</td>
<td>{studentDataRow.section}</td>
<td>{studentDataRow.batch}</td>
<td>{studentDataRow.contact_no}</td>
</tr>
))}
</tbody>
</table>
);
}
}
以下是来自API的数据:
[{"_id":"5d0cd67416c3a60017608a48","type":"student","name":"Samnan","contact_no":"9999","class":"123","section":"av","batch":"2002","__v":0},
{"_id":"5d0d1a7bfe72ac001775d778","type":"student","name":"as","contact_no":"0","class":"d","section":"r","batch":"a","__v":0},
{"_id":"5d0d1b24fe72ac001775d779","type":"student","name":"ab","contact_no":"0","class":"d","section":"afrgr","batch":"adsda","__v":0},
{"_id":"5d0d1b58259c5d6cd69acf3b","type":"student","name":"akash","contact_no":"567","class":"23","section":"h","batch":"2012","__v":0},
{"_id":"5d0ea1eb91eac20017f36739","type":"student","name":"as","contact_no":"08109209","class":"v","section":"qere","batch":"re","__v":0}]
要在本地重现此问题:
git clone https://github.com/Geektrovert/EduSys.git && cd EduSys
npm i
npm run dev
答案 0 :(得分:1)
我做了一些更改以使其运行。 getInitialProps
似乎没有被调用。我将您的API调用移至componentDidMount
中,并使用该状态存储了学生数据。
import React, { Component } from "react";
import fetch from "isomorphic-unfetch";
export default class extends Component {
constructor(props) {
super(props);
this.state = {
studentData: []
};
}
async componentDidMount() {
const res = await fetch("https://edusys-yas.herokuapp.com/api/students");
const studentData = await res.json();
this.setState({ studentData });
}
render() {
return (
<table className="table is-striped is-narrow is-fullwidth">
<thead>
<tr>
<th>Name</th>
<th>Class</th>
<th>Section</th>
<th>Batch</th>
<th>Contact No.</th>
</tr>
</thead>
<tbody>
{this.state.studentData.map(studentDataRow => (
<tr>
<td>{studentDataRow.name}</td>
<td>{studentDataRow.class}</td>
<td>{studentDataRow.section}</td>
<td>{studentDataRow.batch}</td>
<td>{studentDataRow.contact_no}</td>
</tr>
))}
</tbody>
</table>
);
}
}