Xamarin.Android之封装个简单的网络请求类

一、前言

回忆到上篇 《Xamarin.Android再体验之简单的登录Demo》 做登录时，用的是GET的请求，还用的是同步，

于是现在将其简单的改写，做了个简单的封装，包含基于HttpClient和HttpWebRequest两种方式的封装。

由于对这一块还不是很熟悉，所以可能不是很严谨。

二、先上封装好的代码

 using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Json;
 using System.Linq;
 using System.Net;
 using System.Net.Http;
 using System.Text;
 using System.Threading.Tasks;

 namespace Catcher.AndroidDemo.Common
 {
     public static class EasyWebRequest
     {
         /// <summary>
         /// send the post request based on HttpClient
         /// </summary>
         /// <param name="requestUrl">the url you post</param>
         /// <param name="routeParameters">the parameters you post</param>
         /// <returns>return a response object</returns>
         public static async Task<object> SendPostRequestBasedOnHttpClient(string requestUrl, IDictionary<string, string> routeParameters)
         {
             object returnValue = new object();
             HttpClient client = new HttpClient();
             client.MaxResponseContentBufferSize = ;
             Uri uri = new Uri(requestUrl);
             var content = new FormUrlEncodedContent(routeParameters);
             try
             {
                 var response = await client.PostAsync(uri, content);
                 if (response.IsSuccessStatusCode)
                 {
                     var stringValue = await response.Content.ReadAsStringAsync();
                     returnValue = JsonObject.Parse(stringValue);
                 }
             }
             catch (Exception ex)
             {
                 throw ex;
             }
             return returnValue;
         }

         /// <summary>
         /// send the get request based on HttpClient
         /// </summary>
         /// <param name="requestUrl">the url you post</param>
         /// <param name="routeParameters">the parameters you post</param>
         /// <returns>return a response object</returns>
         public static async Task<object> SendGetRequestBasedOnHttpClient(string requestUrl, IDictionary<string, string> routeParameters)
         {
             object returnValue = new object();
             HttpClient client = new HttpClient();
             client.MaxResponseContentBufferSize = ;
             //format the url paramters
             string paramters = string.Join("&", routeParameters.Select(p => p.Key + "=" + p.Value));
             Uri uri = new Uri(string.Format("{0}?{1}", requestUrl, paramters));
             try
             {
                 var response = await client.GetAsync(uri);
                 if (response.IsSuccessStatusCode)
                 {
                     var stringValue = await response.Content.ReadAsStringAsync();
                     returnValue = JsonObject.Parse(stringValue);
                 }
             }
             catch (Exception ex)
             {
                 throw ex;
             }
             return returnValue;
         }

         /// <summary>
         /// send the get request based on HttpWebRequest
         /// </summary>
         /// <param name="requestUrl">the url you post</param>
         /// <param name="routeParameters">the parameters you post</param>
         /// <returns>return a response object</returns>
         public static async Task<object> SendGetHttpRequestBaseOnHttpWebRequest(string requestUrl, IDictionary<string, string> routeParameters)
         {
             object returnValue = new object();
             string paramters = string.Join("&", routeParameters.Select(p => p.Key + "=" + p.Value));
             Uri uri = new Uri(string.Format("{0}?{1}", requestUrl, paramters));
             var request = (HttpWebRequest)HttpWebRequest.Create(uri);

             using (var response = request.GetResponseAsync().Result as HttpWebResponse)
             {
                 if (response.StatusCode == HttpStatusCode.OK)
                 {
                     using (Stream stream = response.GetResponseStream())
                     {
                         using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))
                         {
                             string stringValue = await reader.ReadToEndAsync();
                             returnValue = JsonObject.Parse(stringValue);
                         }
                     }
                 }
             }
             return returnValue;
         }

         /// <summary>
         /// send the post request based on httpwebrequest
         /// </summary>
         /// <param name="url">the url you post</param>
         /// <param name="routeParameters">the parameters you post</param>
         /// <returns>return a response object</returns>
         public static async Task<object> SendPostHttpRequestBaseOnHttpWebRequest(string url, IDictionary<string, string> routeParameters)
         {
             object returnValue = new object();

             HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
             request.Method = "POST";

             byte[] postBytes = null;
             request.ContentType = "application/x-www-form-urlencoded";
             string paramters = string.Join("&", routeParameters.Select(p => p.Key + "=" + p.Value));
             postBytes = Encoding.UTF8.GetBytes(paramters.ToString());

             using (Stream outstream = request.GetRequestStreamAsync().Result)
             {
                 outstream.Write(postBytes, , postBytes.Length);
             }

             using (HttpWebResponse response = request.GetResponseAsync().Result as HttpWebResponse)
             {
                 if (response.StatusCode == HttpStatusCode.OK)
                 {
                     using (Stream stream = response.GetResponseStream())
                     {
                         using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))
                         {
                             string stringValue = await reader.ReadToEndAsync();
                             returnValue = JsonObject.Parse(stringValue);
                         }
                     }
                 }
             }
             return returnValue;
         }
     }
 }

需要说明一下的是，我把这个方法当做一个公共方法抽离到一个单独的类库中

三、添加两个数据服务的方法

         [HttpPost]
         public ActionResult PostThing(string str)
         {
             var json = new
             {
                 Code ="",
                 Msg = "OK",
                 Val = str
             };
             return Json(json);
         }

         public ActionResult GetThing(string str)
         {
             var json = new
             {
                 Code = "",
                 Msg = "OK",
                 Val = str
             };
             return Json(json,JsonRequestBehavior.AllowGet);
         }

这两个方法，一个是为了演示post，一个是为了演示get

部署在本地的IIS上便于测试！

四、添加一个Android项目，测试我们的方法

先来看看页面，一个输入框，四个按钮，这四个按钮分别对应一种请求。

然后是具体的Activity代码

 using System;
 using Android.App;
 using Android.Content;
 using Android.Runtime;
 using Android.Views;
 using Android.Widget;
 using Android.OS;
 using System.Collections.Generic;
 using Catcher.AndroidDemo.Common;
 using System.Json;

 namespace Catcher.AndroidDemo.EasyRequestDemo
 {
     [Activity(Label = "简单的网络请求Demo", MainLauncher = true, Icon = "@drawable/icon")]
     public class MainActivity : Activity
     {
         EditText txtInput;
         Button btnPost;
         Button btnGet;
         Button btnPostHWR;
         Button btnGetHWR;
         TextView tv;

         protected override void OnCreate(Bundle bundle)
         {
             base.OnCreate(bundle);

             SetContentView(Resource.Layout.Main);

             txtInput = FindViewById<EditText>(Resource.Id.txt_input);
             btnPost = FindViewById<Button>(Resource.Id.btn_post);
             btnGet = FindViewById<Button>(Resource.Id.btn_get);
             btnGetHWR = FindViewById<Button>(Resource.Id.btn_getHWR);
             btnPostHWR = FindViewById<Button>(Resource.Id.btn_postHWR);
             tv = FindViewById<TextView>(Resource.Id.tv_result);

             //based on httpclient
             btnPost.Click += PostRequest;
             btnGet.Click += GetRequest;
             //based on httpwebrequest
             btnPostHWR.Click += PostRequestByHWR;
             btnGetHWR.Click += GetRequestByHWR;
         }

         private async void GetRequestByHWR(object sender, EventArgs e)
         {
             string url = "http://192.168.1.102:8077/User/GetThing";
             IDictionary<string, string> routeParames = new Dictionary<string, string>();
             routeParames.Add("str", this.txtInput.Text);
             var result = await EasyWebRequest.SendGetHttpRequestBaseOnHttpWebRequest(url, routeParames);
             var data = (JsonObject)result;
             this.tv.Text = "hey," + data["Val"] + ",  i am from httpwebrequest get";
         }

         private async void PostRequestByHWR(object sender, EventArgs e)
         {
             string url = "http://192.168.1.102:8077/User/PostThing";
             IDictionary<string, string> routeParames = new Dictionary<string, string>();
             routeParames.Add("str", this.txtInput.Text);
             var result = await EasyWebRequest.SendPostHttpRequestBaseOnHttpWebRequest(url, routeParames);
             var data = (JsonObject)result;
             this.tv.Text = "hey," + data["Val"] + ",  i am from httpwebrequest post";
         }

         private async void PostRequest(object sender, EventArgs e)
         {
             string url = "http://192.168.1.102:8077/User/PostThing";
             IDictionary<string, string> routeParames = new Dictionary<string, string>();
             routeParames.Add("str", this.txtInput.Text);
             var result = await EasyWebRequest.SendPostRequestBasedOnHttpClient(url, routeParames);
             var data = (JsonObject)result;
             this.tv.Text = "hey," + data["Val"] + ",  i am from httpclient post";
         }

         private async void GetRequest(object sender, EventArgs e)
         {
             string url = "http://192.168.1.102:8077/User/GetThing";
             IDictionary<string, string> routeParames = new Dictionary<string, string>();
             routeParames.Add("str", this.txtInput.Text);
             var result = await EasyWebRequest.SendGetRequestBasedOnHttpClient(url, routeParames);
             var data = (JsonObject)result;
             this.tv.Text = "hey," + data["Val"] + ",  i am from httpclient get";
         }
     }
 }

OK，下面看看效果图

      

如果那位大哥知道有比较好用的开源网络框架推荐请告诉我！！

最后放上本次示例的代码：

https://github.com/hwqdt/Demos/tree/master/src/Catcher.AndroidDemo