请求网络获取数据

• 点击按钮发送一个post请求，发送一条string
• 由于此处的返回result.data本身就是一个string，因此不需要转换类型

      Button('请求网络')         .margin({ top: 10 })         .fontSize(24)         .fontWeight(FontWeight.Bold)         .onClick(() => {            httpRequestPost('http://test.xxx', "你好")             .then((result: ResponseResult) => {               console.log("msg=" + result.msg)               console.log("data=" + result.data)               this.message = result.data.toString()             })          }) 

• 如果需要类型转换，可以使用as转换
• result.data as ResponseToken

          httpRequestGet('http://test.xxx')             .then((result: ResponseResult) => {               let data = result.data as ResponseToken               console.log("msg=" + result.msg)               console.log("token=" + data.access_token)             }) 

export class ResponseToken {   access_token: string = "";   expires_in: string = "";   expires_date: string = ""; } 

封装一个HttpUtil

• 对外开放一个httpRequestGet和httpRequestPost，用于get和post请求

 import { http } from '@kit.NetworkKit'; import ResponseResult from './ResponseResult';  /**  * Initiate an HTTP GET request to the specified URL.  */ export function httpRequestGet(url: string) {   return httpRequest(url, http.RequestMethod.GET); }  /**  * Initiate an HTTP POST request to the specified URL.  */ export function httpRequestPost(url: string, newsData: string) {   return httpRequest(url, http.RequestMethod.POST, newsData); }  /**  * Initiates an HTTP request to a given URL.  *  * @param url URL for initiating an HTTP request  * @param method Request method.  * @param extraData Additional data of the request.  * @returns Returns {@link ResponseResult}.  */ function httpRequest(url: string, method: http.RequestMethod, params?: string): Promise {   let httpRequest = http.createHttp();   let responseResult = httpRequest.request(url, {     method: method,     header: {       'Content-Type': 'application/json'     },     extraData: params   });   let serverData = new ResponseResult();   // Processes the data and returns.   return responseResult.then((value: http.HttpResponse) => {     if (value.responseCode === 200) {       // Obtains the returned data.       let result = `${value.result}`;       let resultJson: ResponseResult = JSON.parse(result);       if (resultJson.code === '000000') {         serverData.data = resultJson.data;       }       serverData.code = resultJson.code;       serverData.msg = resultJson.msg;     } else {       serverData.msg = `Network request failed, please try later!&${value.responseCode}`;     }     return serverData;   }).catch(() => {     serverData.msg = 'Network request failed, please try later!';     return serverData;   }); } 

• ResponseResult为服务端返回的基本结构

 export default class ResponseResult {   /**    * Code returned by the network request: success, fail.    */   code: string;    /**    * Message returned by the network request.    */   msg: string | Resource;    /**    * Data returned by the network request.    */   data: string | Object | ArrayBuffer;    constructor() {     this.code = '';     this.msg = '';     this.data = '';   }  }