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 = 256000;
            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 = 256000;
            //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, 0, 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 ="00000",
                Msg = "OK",
                Val = str
            };
            return Json(json);
        }

        public ActionResult GetThing(string str)
        {
            var json = new
            {
                Code = "00000",
                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