鸿蒙 ark ui 网络请求我不允许你不会-编程知识

前言：

最近有在学习这个鸿蒙的ark ui开发因为鸿蒙不是发布了一个鸿蒙next的测试版本明年会启动纯血鸿蒙应用所以我就想提前给大家写一些博客文章

效果图

11-24 16:26:22.005 25156-25156/com.example.httpsrequest E A0ff00/HTTPS: 请求状态 --> 200, %{public}s
11-24 16:26:22.006 25156-25156/com.example.httpsrequest E A0ff00/HTTPS: 请求成功, %{public}s
11-24 16:26:22.006 25156-25156/com.example.httpsrequest E A0ff00/HTTPS: 请求返回数据, "{\"ret\":1,\"data\":[{\"id\":\"8289\",\"title\":\"\\u6cb9\\u7116\\u5927\\u867e\",\"pic\":\"http:\\/\\/www.qubaobei.com\\/ios\\/cf\\/uploadfile\\/132\\/9\\/8289.jpg\",\"collect_num\":\"1670\",\"food_str\":\"\\u5927\\u867e \\u8471 \\u751f\\u59dc \\u690d\\u7269\\u6cb9 \\u6599\\u9152\",\"num\":1670},{\"id\":\"2127\",\"title\":\"\\u56db\\u5ddd\\u56de\\u9505\\u8089\",\"pic\":\"http:\\/\\/www.qubaobei.com\\/ios\\/cf\\/uploadfile\\/132\\/3\\/2127.jpg\",\"collect_num\":\"1592\",\"food_str\":\"\\u732a\\u8089 \\u9752\\u849c \\u9752\\u6912 \\u7ea2\\u6912 \\u59dc\\u7247\",\"num\":1592},{\"id\":\"30630\",\"title\":\"\\u8d85\\u7b80\\u5355\\u8292\\u679c\\u5e03\\u4e01\",\"pic\":\"http:\\/\\/www.qubaobei.com\\/ios\\/cf\\/uploadfile\\/132\\/31\\/30630.jpg\",\"collect_num\":\"1552\",\"food_str\":\"QQ\\u7cd6 \\u725b\\u5976 \\u8292\\u679c\",\"num\":1552},{\"id\":\"9073\",\"title\":\"\\u5bb6\\u5e38\\u7ea2\\u70e7\\u9c7c\",\"pic\":\"http:\\/\\/www.qubaobei.com\\/ios\\/cf\\/uploadfile\\/132\\/10\\/9073.jpg\",\"co

具体实现：

添加网络访问权限：

在module.json5 里面添加网络访问权限

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

创建HTTPS请求

HTTPS协议是位于应用层的一种安全传输协议，与HTTP最大的区别是服务端与客户端之间进行数据传输都会经过TLS/SSL加密。该示例请求测试接口地址，并将请求得到的再日志里面打印出来。效果如图所示：

请求工具类

首先在OkHttpUtil.ets中调用createHttp方法创建一个请求任务，再通过request方法发起网络请求。该方法支持三个参数：url、options以及callback回调，其中options可以设置请求方法、请求头以及超时时间等。

import http from '@ohos.net.http';
import Constants, { ContentType } from '../constant/Constants';
import Logger from './Logger';
import { NewsData } from '../viewmodel/NewsData';export function httpRequestGet(url: string) {return httpRequest(url, http.RequestMethod.GET);
}export function httpRequestPost(url: string, params?: NewsData) {return httpRequest(url, http.RequestMethod.POST, params);
}function httpRequest(url: string, method: http.RequestMethod,params?: NewsData){let httpRequest = http.createHttp();let responseResult = httpRequest.request(url, {method: method,readTimeout: Constants.HTTP_READ_TIMEOUT,//读取超时时间 可选，默认为60000msheader: {'Content-Type': ContentType.JSON},connectTimeout: Constants.HTTP_READ_TIMEOUT,//连接超时时间  可选，默认为60000msextraData: params // 请求参数});return responseResult.then((value: http.HttpResponse)=>{Logger.error("请求状态 --> "+value.responseCode)if(value.responseCode===200){Logger.error("请求成功");let getresult = value.result;Logger.error('请求返回数据', JSON.stringify(getresult));return getresult;}}).catch((err)=>{return "";});
}

日志工具类

/** Copyright (c) 2023 Huawei Device Co., Ltd.* Licensed under the Apache License, Version 2.0 (the "License");* you may not use this file except in compliance with the License.* You may obtain a copy of the License at**     http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an "AS IS" BASIS,* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.* See the License for the specific language governing permissions and* limitations under the License.*/import hilog from '@ohos.hilog';class Logger {private domain: number;private prefix: string;private format: string = '%{public}s, %{public}s';/*** constructor.** @param Prefix Identifies the log tag.* @param domain Domain Indicates the service domain, which is a hexadecimal integer ranging from 0x0 to 0xFFFFF.*/constructor(prefix: string = 'MyApp', domain: number = 0xFF00) {this.prefix = prefix;this.domain = domain;}debug(...args: string[]): void {hilog.debug(this.domain, this.prefix, this.format, args);}info(...args: string[]): void {hilog.info(this.domain, this.prefix, this.format, args);}warn(...args: string[]): void {hilog.warn(this.domain, this.prefix, this.format, args);}error(...args: string[]): void {hilog.error(this.domain, this.prefix, this.format, args);}
}export default new Logger('HTTPS', 0xFF00)

然后在view中展示去点击触发请求

import webView from '@ohos.web.webview';
import http from '@ohos.net.http';
import httpGet from '../common/utils/HttpUtil';
import StyleConstant from '../common/constant/StyleConstant';
import CommonConstant from '../common/constant/CommonConstants';
import { httpRequestGet }  from '../common/utils/OKhttpUtil';@Entry
@Component
struct WebPage {controller: webView.WebviewController = new webView.WebviewController();@State buttonName: Resource = $r('app.string.request_button_name');@State webVisibility: Visibility = Visibility.Hidden;@State webSrc: string = CommonConstant.DISH;build() {Column() {Row() {Image($r('app.media.ic_network_global')).height($r('app.float.image_height')).width($r('app.float.image_width'))TextInput({ placeholder: $r('app.string.input_address'), text: this.webSrc }).height($r('app.float.text_input_height')).layoutWeight(1).backgroundColor(Color.White).onChange((value: string) => {this.webSrc = value;})}.margin({top: $r('app.float.default_margin'),left: $r('app.float.default_margin'),right: $r('app.float.default_margin')}).height($r('app.float.default_row_height')).backgroundColor(Color.White).borderRadius($r('app.float.border_radius')).padding({left: $r('app.float.default_padding'),right: $r('app.float.default_padding')})Row() {Web({ src: this.webSrc, controller: this.controller }).zoomAccess(true).height(StyleConstant.FULL_HEIGHT).width(StyleConstant.FULL_WIDTH)}.visibility(this.webVisibility).height(StyleConstant.WEB_HEIGHT).width(StyleConstant.FULL_WIDTH).align(Alignment.Top)Row() {Button(this.buttonName).fontSize($r('app.float.button_font_size')).width(StyleConstant.BUTTON_WIDTH).height($r('app.float.button_height')).fontWeight(FontWeight.Bold).onClick(() => {this.onRequest();})}.height($r('app.float.default_row_height'))}.width(StyleConstant.FULL_WIDTH).height(StyleConstant.FULL_HEIGHT).backgroundImage($r('app.media.ic_background_image', ImageRepeat.NoRepeat)).backgroundImageSize(ImageSize.Cover)}async onRequest() {httpRequestGet(CommonConstant.DISH).then((data)=>{console.log("data --- > "+data);});}
}

分析模块源码可知，通过request方法建立请求后，模块底层首先会调用三方库 libcurl 中的curl_easy_init初始化一个简单会话。初始化完成后，接着调用curl_easy_setopt方法设置传输选项。其中CURLOPT_URL用于设置请求的URL地址，对应request中的url参数；CURLOPT_WRITEFUNCTION可以设置一个回调，保存接收的数据；CURLOPT_HEADERDATA支持设置回调，在回调中保存响应头数据。

传输选项设置成功后，调用curl_multi_perform执行传输请求，并通过curl_multi_info_read查询处理句柄是否有消息返回，最后进入HandleCurlData方法处理返回数据。