怎么创建网站相册学动漫设计需要什么条件

基本使用

鸿蒙应用发起HTTP请求的基本使用，如下：

• 导入http模块
• 创建httpRequest对象
• 发起http请求，并处理响应结果

第一、导入http模块：

import http from '@ohos.net.http'

第二、创建httpRequest对象，注意的是每一个httpRequest对象对应一个http请求任务，不可复用。

 const httpRequest = http.createHttp()

第三、发起请求，比如POST请求

 httpRequest.request(// 请求url地址url,{// 请求方式method: http.RequestMethod.POST,// 请求的额外数据。extraData: {"param1": "value1","param2": "value2",},// 可选，默认为60sconnectTimeout: 60000,// 可选，默认为60sreadTimeout: 60000,// 开发者根据自身业务需要添加header字段header: {'Content-Type': 'application/json'}}).then((data) => { if (data.responseCode === http.ResponseCode.OK) {// 处理响应结果// data.result为服务器返回的业务数据console.info('Result:' + data.result);console.info('code:' + data.responseCode);}
}).catch((err) => {console.info('error:' + JSON.stringify(err));
});

最后需要声明网络权限，在module.josn5文件中声明：

{"module" : {"requestPermissions":[{"name": "ohos.permission.INTERNET"}]}
}

上面就是网络请求的简单使用，接下来通过Promise来封装一个网络请求库，统一管理请求参数、响应数据、日志的输出等，对外屏蔽了细节，使用者只需定义业务数据的实体类以及调用即可。

封装

以**玩Android**开放接口为测试用例

定义业务数据的实体类，通过泛型来接收不同的数据类型：

export class ResponseResult<T> {errorCode: number;errorMsg: string;data?: T | Object | string;
}

把各种请求方式用枚举声明RequestMethod

export enum RequestMethod {OPTIONS,GET,HEAD,POST ,PUT,DELETE,TRACE,CONNECT
}

其实在http模块中已经有对应的枚举，之所以再用一个新枚举来声明，是简化使用，同时也是将http模块相关细节屏蔽掉不对外开放，这样可以灵活替换网络库。

定义一个HttpUtils类实现：

const  TAG = "HttpUtils"
const BASE_URL = "https://www.wanandroid.com"
export class HttpUtils{public static readonly SUCCESS_CODE: number = 0public static readonly READ_TIME_OUT = 60 * 1000public static readonly CONNECT_TIME_OUT = 60 * 1000private baseUrl: string = ""constructor(baseUrl: string) {this.baseUrl = baseUrl}private methodName(method: RequestMethod): http.RequestMethod {switch (method){case RequestMethod.OPTIONS:{return http.RequestMethod.OPTIONS}case RequestMethod.GET:{return http.RequestMethod.GET}case RequestMethod.HEAD:{return http.RequestMethod.HEAD}case RequestMethod.POST:{return http.RequestMethod.POST}case RequestMethod.PUT:{return http.RequestMethod.PUT}case RequestMethod.DELETE:{return http.RequestMethod.DELETE}case RequestMethod.TRACE:{return http.RequestMethod.TRACE}case RequestMethod.CONNECT:{return http.RequestMethod.CONNECT}}}request<T>(path: string, reqMethod: RequestMethod, parameter: Map<string, Object> = null): Promise<T | null> {// 注意的是每一个httpRequest对象对应一个http请求任务，不可复用。const httpRequest = http.createHttp()const method = this.methodName(reqMethod)let extraData = {}let url = `${this.baseUrl}/${path}`if (parameter != null) {switch (reqMethod) {case RequestMethod.POST: {extraData = Object.fromEntries(parameter)break;}case RequestMethod.GET: {const urlParams = Object.keys(parameter).map(key => `${key}=${parameter[key]}`).join('&')if (url.includes("?")) {url = `${url}${urlParams}`} else {url = `${url}?${urlParams}`}break;}}}LogUtils.debug(TAG, "==================Request====================")LogUtils.debug(TAG, "url: " + url)LogUtils.debug(TAG, "method: " + method.toString())if (reqMethod == RequestMethod.POST)LogUtils.debug(TAG, "extraData: " + JSON.stringify(parameter, null, 2))return new Promise((resolve, reject) => {httpRequest.request(url,{method,readTimeout: HttpUtils.READ_TIME_OUT,connectTimeout: HttpUtils.CONNECT_TIME_OUT,header: {'Content-Type': 'application/json'},extraData}).then((value) => {LogUtils.debug(TAG, "==================Response====================")LogUtils.debug(TAG, "url: " + url)LogUtils.debug(TAG, "method: " + method.toString())LogUtils.debug(TAG, "header: " + JSON.stringify(value.header, null, 2))LogUtils.debug(TAG, "responseCode: " + value.responseCode)LogUtils.debug(TAG, "resultType: " + value.resultType)if (value.responseCode == http.ResponseCode.OK) {let result: ResponseResult<T> = JSON.parse(value.result.toString())LogUtils.debug(TAG, "body: " + JSON.stringify(result, null, 2))if (result.errorCode == HttpUtils.SUCCESS_CODE) {resolve(result.data as T)} else {reject(result.errorMsg)}} else {reject("请求失败")}}).catch((reason) => {reject(reason)})})}get<T>(path: string, parameter: Map<string, Object> = null): Promise<T | null> {return this.request<T>(path, RequestMethod.GET, parameter)}post<T>(path: string, parameter: Map<string, Object> = null): Promise<T | null> {return this.request<T>(path, RequestMethod.POST, parameter)}delete<T>(path: string, parameter: Map<string, Object> = null): Promise<T | null> {return this.request<T>(path, RequestMethod.DELETE, parameter)}put<T>(path: string, parameter: Map<string, Object> = null): Promise<T | null> {return this.request<T>(path, RequestMethod.PUT, parameter)}}
const YiNet = new HttpUtils(BASE_URL)
export default YiNet

使用发起网络请求：

  aboutToAppear() {let map = new Map<string,string>()map["cid"] = 294YiNet.get<ArticleList>("project/list/1/json",map).then((data)=>{this.data = JSON.stringify(data, null, 2)})let map2 = new Map<string,string>()map2["username"] = "123"map2["password"] = "123456"YiNet.post<User>("user/login",map2).then((data)=>{this.data = JSON.stringify(data, null, 2)}).catch((err)=>{Prompt.showToast({message:err})})}

日志输出：

参考

• https://developer.huawei.com/consumer/cn/training/course/slightMooc/C101667364948559963?ha_linker=eyJ0cyI6MTcwMjE3NzI3OTYyMywiaWQiOiI4MmM3ZTI1MmFmMDJlMDZiODBmOGU1ZDM5ZTI5YmMyOCJ9
• https://www.wanandroid.com/blog/show/2