原文:
重新想象 Windows 8.1 Store Apps (90) - 通信的新特性: 通过 HttpBaseProtocolFilter 实现 http 请求的缓存控制,以及 cookie 读写; 自定义 HttpFilter; 其他
重新想象 Windows 8.1 Store Apps (90) - 通信的新特性: 通过 HttpBaseProtocolFilter 实现 http 请求的缓存控制,以及 cookie 读写; 自定义 HttpFilter; 其他
作者:webabcd
介绍
重新想象 Windows 8.1 Store Apps 之通信的新特性
- 通过 HttpBaseProtocolFilter 控制缓存逻辑,以及如何通过 HttpBaseProtocolFilter 管理 cookie
- 自定义 HttpFilter
- 其他
示例
HTTP 服务端
WebServer/HttpDemo.aspx.cs
/* * 用于响应 http 请求 */ using System; using System.IO; using System.Threading; using System.Web; namespace WebServer { public partial class HttpDemo : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { // 停 3 秒,以方便测试 http 请求的取消 Thread.Sleep(3000); var action = Request.QueryString["action"]; switch (action) { case "getString": // 响应 http get string Response.Write("hello webabcd: " + DateTime.Now.ToString("hh:mm:ss")); break; case "getStream": // 响应 http get stream Response.Write("hello webabcd hello webabcd hello webabcd hello webabcd hello webabcd hello webabcd hello webabcd hello webabcd hello webabcd hello webabcd hello webabcd hello webabcd"); break; case "postString": // 响应 http post string Response.Write(string.Format("param1:{0}, param2:{1}, referrer:{2}", Request.Form["param1"], Request.Form["param2"], Request.UrlReferrer)); break; case "postStream": // 响应 http post stream using (StreamReader reader = new StreamReader(Request.InputStream)) { if (Request.InputStream.Length > 1024 * 100) { // 接收的数据太大,则显示“数据接收成功” Response.Write("数据接收成功"); } else { // 显示接收到的数据 string body = reader.ReadToEnd(); Response.Write(Server.HtmlEncode(body)); } } break; case "uploadFile": // 处理上传文件的请求 for (int i = 0; i < Request.Files.Count; i++) { string key = Request.Files.GetKey(i); HttpPostedFile file = Request.Files.Get(key); string savePath = @"d:\" + file.FileName; // 保存文件 file.SaveAs(savePath); Response.Write(string.Format("key: {0}, fileName: {1}, savePath: {2}", key, file.FileName, savePath)); Response.Write("\n"); } break; case "outputCookie": // 用于显示服务端获取到的 cookie 信息 for (int i = 0; i < Request.Cookies.Count; i++) { HttpCookie cookie = Request.Cookies[0]; Response.Write(string.Format("cookieName: {0}, cookieValue: {1}", cookie.Name, cookie.Value)); Response.Write("\n"); } break; case "outputCustomHeader": // 用于显示一个自定义的 http header Response.Write("myRequestHeader: " + Request.Headers["myRequestHeader"]); break; default: break; } Response.End(); } } }
1、演示如何通过 HttpBaseProtocolFilter 控制缓存逻辑,以及如何通过 HttpBaseProtocolFilter 管理 cookie
HttpBaseProtocolFilterDemo.xaml
<Page x:Class="Windows81.Communication.HTTP.HttpBaseProtocolFilterDemo" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="using:Windows81.Communication.HTTP" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d"> <Grid Background="Transparent"> <StackPanel Margin="120 0 0 0"> <TextBlock Name="lblMsg" FontSize="14.667" /> <Button Name="btnCacheControl" Content="通过 HttpBaseProtocolFilter 控制缓存逻辑" Click="btnCacheControl_Click" Margin="0 10 0 0" /> <Button Name="btnCookie" Content="通过 HttpBaseProtocolFilter 管理 cookie" Click="btnCookie_Click" Margin="0 10 0 0" /> </StackPanel> </Grid> </Page>
HttpBaseProtocolFilterDemo.xaml.cs
/* * 演示如何通过 HttpBaseProtocolFilter 控制缓存逻辑,以及如何通过 HttpBaseProtocolFilter 管理 cookie * * * 注: * 1、HttpBaseProtocolFilter 实现了 IHttpFilter 接口(也就是说如果想要一个自定义 HttpFilter 的话,只要实现 IHttpFilter 接口即可) * 2、本例仅演示通过 HttpBaseProtocolFilter 控制缓存逻辑以及管理 cookie,HttpBaseProtocolFilter 的其它功能请参见文档 */ using System; using Windows.UI.Xaml; using Windows.UI.Xaml.Controls; using Windows.UI.Xaml.Navigation; using Windows.Web.Http; using Windows.Web.Http.Filters; namespace Windows81.Communication.HTTP { public sealed partial class HttpBaseProtocolFilterDemo : Page { private HttpClient _httpClient; private HttpBaseProtocolFilter _filter; public HttpBaseProtocolFilterDemo() { this.InitializeComponent(); } protected override void OnNavigatedFrom(NavigationEventArgs e) { // 释放资源 if (_filter != null) { _filter.Dispose(); _filter = null; } if (_httpClient != null) { _httpClient.Dispose(); _httpClient = null; } } // 演示如何通过 HttpBaseProtocolFilter 控制缓存逻辑 private async void btnCacheControl_Click(object sender, RoutedEventArgs e) { _filter = new HttpBaseProtocolFilter(); // 实例化 HttpClient 时,指定此 HttpClient 所关联的 IHttpFilter 对象 _httpClient = new HttpClient(_filter); try { // 获取到 http 响应的数据后写入缓存的行为 // NoCache - 不写入缓存 // Default - 默认行为,一般会写入缓存(默认值) _filter.CacheControl.WriteBehavior = HttpCacheWriteBehavior.NoCache; // 请求 http 时,从缓存获取数据的逻辑 // Default - 使用 RFC 2616 中由 IETF 指定的缓存算法(默认值) // MostRecent - 尽可能使用本地 HTTP 缓存,但应始终询问服务器是否有更新的内容可用 // OnlyFromCache - 只使用本地 HTTP 缓存中的数据,适合脱机的场景 _filter.CacheControl.ReadBehavior = HttpCacheReadBehavior.Default; HttpResponseMessage response = await _httpClient.GetAsync(new Uri("http://localhost:39630/HttpDemo.aspx?action=getString")); lblMsg.Text += ((int)response.StatusCode) + " " + response.ReasonPhrase; lblMsg.Text += Environment.NewLine; lblMsg.Text += await response.Content.ReadAsStringAsync(); lblMsg.Text += Environment.NewLine; } catch (Exception ex) { lblMsg.Text += ex.ToString(); lblMsg.Text += Environment.NewLine; } } // 演示如何通过 HttpBaseProtocolFilter 管理 cookie private async void btnCookie_Click(object sender, RoutedEventArgs e) { _httpClient = new HttpClient(); try { // 构造一个 cookie(需要指定 cookie 的 name, domain, path) HttpCookie cookie = new HttpCookie("name", "localhost", "/"); cookie.Value = "webabcd"; cookie.Expires = DateTimeOffset.Now.AddDays(1); cookie.Secure = false; cookie.HttpOnly = false; // 通过 HttpBaseProtocolFilter 写入 cookie(也可以获取 cookie 或者删除 cookie) HttpBaseProtocolFilter filter = new HttpBaseProtocolFilter(); bool replaced = filter.CookieManager.SetCookie(cookie, false); // 请求 http 时会带上相应的 cookie HttpResponseMessage response = await _httpClient.GetAsync(new Uri("http://localhost:39630/HttpDemo.aspx?action=outputCookie")); lblMsg.Text += ((int)response.StatusCode) + " " + response.ReasonPhrase; lblMsg.Text += Environment.NewLine; lblMsg.Text += await response.Content.ReadAsStringAsync(); lblMsg.Text += Environment.NewLine; } catch (Exception ex) { lblMsg.Text += ex.ToString(); lblMsg.Text += Environment.NewLine; } } } }
2、演示如何使用自定义的 HttpFilter
MyHttpFilter.cs
/* * 实现 IHttpFilter 接口,开发一个自定义的 HttpFilter * * * 本 HttpFilter 会在请求和响应的 http header 中添加一条自定义数据 */ using System; using System.Runtime.InteropServices.WindowsRuntime; using Windows.Foundation; using Windows.Web.Http; using Windows.Web.Http.Filters; namespace Windows81.Communication.HTTP { public class MyHttpFilter : IHttpFilter { private HttpBaseProtocolFilter _innerFilter; public MyHttpFilter() { _innerFilter = new HttpBaseProtocolFilter(); } // IHttpFilter 唯一的一个需要实现的方法 public IAsyncOperationWithProgress<HttpResponseMessage, HttpProgress> SendRequestAsync(HttpRequestMessage request) { return AsyncInfo.Run<HttpResponseMessage, HttpProgress>(async (cancellationToken, progress) => { // 添加一个自定义 request http header request.Headers.Add("myRequestHeader", "request webabcd"); // 借用 HttpBaseProtocolFilter 来完成 SendRequestAsync() 的工作 HttpResponseMessage response = await _innerFilter.SendRequestAsync(request).AsTask(cancellationToken, progress); cancellationToken.ThrowIfCancellationRequested(); // 添加一个自定义 response http header response.Headers.Add("myResponseHeader", "response webabcd"); return response; }); } public void Dispose() { _innerFilter.Dispose(); GC.SuppressFinalize(this); } } }
CustomHttpFilter.xaml
<Page x:Class="Windows81.Communication.HTTP.CustomHttpFilter" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="using:Windows81.Communication.HTTP" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d"> <Grid Background="Transparent"> <StackPanel Margin="120 0 0 0"> <TextBlock Name="lblMsg" FontSize="14.667" /> <Button Name="btnDemo" Content="自定义 HttpFilter" Click="btnDemo_Click" Margin="0 10 0 0" /> <Button Name="btnCancel" Content="cancel" Click="btnCancel_Click" Margin="0 10 0 0" /> </StackPanel> </Grid> </Page>
CustomHttpFilter.xaml.cs
/* * 演示如何使用自定义的 HttpFilter * * * 自定义 HttpFilter 需要实现 IHttpFilter 接口,请参见:MyHttpFilter.cs */ using System; using System.Threading; using System.Threading.Tasks; using Windows.UI.Xaml; using Windows.UI.Xaml.Controls; using Windows.UI.Xaml.Navigation; using Windows.Web.Http; namespace Windows81.Communication.HTTP { public sealed partial class CustomHttpFilter : Page { private HttpClient _httpClient; private CancellationTokenSource _cts; // 自定义的 HttpFilter private MyHttpFilter _filter; public CustomHttpFilter() { this.InitializeComponent(); } protected override void OnNavigatedFrom(NavigationEventArgs e) { // 释放资源 if (_filter != null) { _filter.Dispose(); _filter = null; } if (_httpClient != null) { _httpClient.Dispose(); _httpClient = null; } if (_cts != null) { _cts.Dispose(); _cts = null; } } private async void btnDemo_Click(object sender, RoutedEventArgs e) { _filter = new MyHttpFilter(); // 实例化 HttpClient 时,指定此 HttpClient 所关联的 IHttpFilter 对象 _httpClient = new HttpClient(_filter); _cts = new CancellationTokenSource(); try { HttpResponseMessage response = await _httpClient.GetAsync(new Uri("http://localhost:39630/HttpDemo.aspx?action=outputCustomHeader")).AsTask(_cts.Token); lblMsg.Text += ((int)response.StatusCode) + " " + response.ReasonPhrase; lblMsg.Text += Environment.NewLine; lblMsg.Text += "myResponseHeader: " + response.Headers["myResponseHeader"]; lblMsg.Text += Environment.NewLine; // IHttpContent.ReadAsStringAsync() - 获取 string 类型的响应数据 // IHttpContent.ReadAsBufferAsync() - 获取 IBuffer 类型的响应数据 // IHttpContent.ReadAsInputStreamAsync() - 获取 IInputStream 类型的响应数据 lblMsg.Text += await response.Content.ReadAsStringAsync(); lblMsg.Text += Environment.NewLine; } catch (TaskCanceledException) { lblMsg.Text += "取消了"; lblMsg.Text += Environment.NewLine; } catch (Exception ex) { lblMsg.Text += ex.ToString(); lblMsg.Text += Environment.NewLine; } } private void btnCancel_Click(object sender, RoutedEventArgs e) { // 取消 http 请求 if (_cts != null) { _cts.Cancel(); _cts.Dispose(); _cts = null; } } } }
3、其他
Other.xaml
<Page x:Class="Windows81.Communication.Other" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="using:Windows81.Communication" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d"> <Grid Background="Transparent"> <StackPanel Margin="120 0 0 0"> <TextBlock Name="lblMsg" FontSize="14.667" TextWrapping="Wrap"> <Run>1、实时通信支持 Windows.Web.Http API 了(仍然要求 app 必须在锁屏上),关于实时通信请参见:http://www.cnblogs.com/webabcd/archive/2013/10/28/3391694.html</Run> <LineBreak /> <Run>2、增加了对 Geofence 的支持,即某设备在进入或退出某地理区域后可以向 app 发出通知。Windows.Devices.Geolocation.Geofencing 命名空间用于 Geofence 管理, LocationTrigger 用于后台任务触发 Geofence 事件</Run> <LineBreak /> <Run>3、支持设备的 WiFi 直连,参见 Windows.Devices.WifiDirect 命名空间</Run> </TextBlock> </StackPanel> </Grid> </Page>
OK
[源码下载]