实现C/S程序的自动更新2

转自:http://blog.csdn.net/danjiewu/article/details/3176001?P_AVPASS=PHDGBITAVPASSP

最近在做一个.Net C/S的系统，需要实现自动更新。MS已经提供了ClickOnce，很方便，但是用起来不太习惯，还是决定自己写一个简单的。

自动更新无非文件比较、下载、启动程序几个步骤，其中文件比较可以通过手动在配置文件中维护版本号，也可以比较文件的MD5值，或者在.Net里还可以用Assembly或文件的版本号。因为怕麻烦，手动维护不考虑，剩下两者各有所长，都提供了以供选择。下载就比较简单了，http、ftp、WebService都可以选择。启动程序一般用System.Diagnostics.Process.Start就可以，我用的是AppDomain.ExecuteAssembly。

要自动生成文件版本信息，需要有个服务端，可以是WebService等等，我采用的是自己实现IHttpHandler，提供文件的版本信息和下载。

下面是UpdateHelper的类图和定义：

 

 

GetUpdateInfos、CheckIfNeedUpdate、DownloadFile分别是获取文件版本信息、比较文件是否是最新的、下载文件的作用，很简单。

     public static class UpdateHelper
     {
         public static UpdateInfo[] GetUpdateInfos()
         {
             HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Properties.Settings.Default.Server);
             request.Method = "GET";
             HttpWebResponse response = (HttpWebResponse)request.GetResponse();
             if (response.StatusCode == HttpStatusCode.OK)
             {
                 using (Stream output = request.GetResponse().GetResponseStream())
                 {
                     XmlSerializer xml = new XmlSerializer(typeof(UpdateInfo[]));
                     return (UpdateInfo[])xml.Deserialize(output);
                 }
             }
             else
             {
                 throw new Exception("Exception occurs on the server.");
             }
         }

         public static bool CheckIfNeedUpdate(UpdateInfo update)
         {
             if (!File.Exists(update.FileName))
             {
                 return true;
             }
             else
             {
                 switch (update.VersionType)
                 {
                     case VersionType.FileVersion:
                         return FileVersionInfo.GetVersionInfo(update.FileName).FileVersion != update.Version;
                     case VersionType.MD5:
                         using (FileStream file = File.OpenRead(update.FileName))
                         {
                             return Convert.ToBase64String(MD5.Create().ComputeHash(file)) != update.Version;
                         }
                     default: return false;
                 }
             }
         }

         public static void Update()
         {
             UpdateInfo[] updates = UpdateHelper.GetUpdateInfos();
             List<Thread> downloadsThreads = new List<Thread>();
             foreach (UpdateInfo update in updates)
             {
                 if (UpdateHelper.CheckIfNeedUpdate(update))
                 {
                     Thread thread = new Thread(delegate(object param) { UpdateHelper.DownloadFile((string)param); });
                     thread.Start(update.FileName);
                     downloadsThreads.Add(thread);
                 }
             }
             foreach (Thread thread in downloadsThreads) thread.Join();
         }

         public static void DownloadFile(string fileName)
         {
             HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Properties.Settings.Default.Server + "?download=" + fileName);
             request.Method = "GET";
             HttpWebResponse response = (HttpWebResponse)request.GetResponse();
             if (response.StatusCode == HttpStatusCode.OK)
             {
                 byte[] buffer = new byte[8096];
                 using (Stream output = request.GetResponse().GetResponseStream())
                 {
                     using (FileStream file = File.Open(fileName, FileMode.OpenOrCreate))
                     {
                         int length = output.Read(buffer, 0, buffer.Length);
                         while (length != 0)
                         {
                             file.Write(buffer, 0, length);
                             length = output.Read(buffer, 0, buffer.Length);
                         }
                     }
                 }
             }
             else
             {
                 throw new Exception("Exception occurs on the server.");
             }
         }
     }

     public class UpdateInfo
     {
         public UpdateInfo() { }

         public UpdateInfo(string filename, VersionType versionType, string version)
         {
             FileName = filename;
             VersionType = versionType;
             Version = version;
         }
         public string FileName;
         public VersionType VersionType;
         public string Version;
     }

     public enum VersionType
     {
         FileVersion,
         MD5
     }

UpdateServiceHandler定义：

  public class UpdateServiceHandler : IHttpHandler
     {
         #region IHttpHandler Members

         public bool IsReusable
         {
             get { return true; }
         }

         public void ProcessRequest(HttpContext context)
         {
             if (String.Equals(context.Request.RequestType, "GET", StringComparison.OrdinalIgnoreCase))
             {
                 string filename = context.Request.QueryString["download"];
                 UpdateInfoSection updateInfoSection = GetUpdateConfig();

                 if (String.IsNullOrEmpty(filename))
                 {
                     context.Response.ContentEncoding = Encoding.UTF8;
                     context.Response.ContentType = "text/xml";
                     foreach (UpdateInfo update in updateInfoSection.UpdateFiles.Values)
                     {
                         switch (update.VersionType)
                         {
                             case VersionType.FileVersion:
                                 update.Version = FileVersionInfo.GetVersionInfo(update.Path).FileVersion;
                                 break;
                             case VersionType.MD5:
                                 using (FileStream file = File.OpenRead(update.Path)) update.Version = Convert.ToBase64String(MD5.Create().ComputeHash(file));
                                 break;
                         }
                     }
                     XmlSerializer xml = new XmlSerializer(typeof(List<UpdateInfo>));
                     xml.Serialize(context.Response.Output, new List<UpdateInfo>(updateInfoSection.UpdateFiles.Values));
                 }
                 else
                 {
                     UpdateInfo update;
                     if (updateInfoSection.UpdateFiles.TryGetValue(filename, out update))
                     {
                         context.Response.ContentEncoding = Encoding.UTF8;
                         context.Response.ContentType = "application/x-msdownload";
                         context.Response.AppendHeader("Content-Disposition", "attachment;filename=" + filename);
                         context.Response.WriteFile(update.Path);
                     }
                     else
                     {
                         context.Response.ContentEncoding = Encoding.UTF8;
                         context.Response.ContentType = "text/html";
                         context.Response.Output.WriteLine("File {0} not fount.", filename);
                     }

                 }
             }
         }

         private UpdateInfoSection GetUpdateConfig()
         {
             UpdateInfoSection updateInfoSection = (UpdateInfoSection)ConfigurationManager.GetSection("ClientUpdateInfo");
             if (!updateInfoSection.Initialize)
             {
                 foreach (UpdateInfo update in updateInfoSection.UpdateFiles.Values)
                 {
                     if (String.IsNullOrEmpty(update.Path)) update.Path = Path.Combine(updateInfoSection.DefaultForlder, update.FileName);
                     update.Path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, update.Path);
                 }
                 updateInfoSection.Initialize = true;
             }
             return updateInfoSection;
         }

         #endregion
     }

     public class UpdateInfoSection : ConfigurationSection
     {
         public string DefaultForlder;
         public Dictionary<string, UpdateInfo> UpdateFiles = new Dictionary<string, UpdateInfo>();
         public bool Initialize = false;

         protected override void DeserializeSection(System.Xml.XmlReader reader)
         {
             while (reader.Read())
             {
                 if (reader.NodeType == System.Xml.XmlNodeType.Element)
                 {
                     switch (reader.Name)
                     {
                         case "File":
                             string versionType = reader.GetAttribute("VersionType");
                             UpdateFiles.Add(reader.GetAttribute("FileName"),
                             new UpdateInfo(
                                 reader.GetAttribute("FileName"),
                                 String.IsNullOrEmpty(versionType) ? VersionType.FileVersion : (VersionType)Enum.Parse(typeof(VersionType), versionType, true),
                                 reader.GetAttribute("Version"),
                                 reader.GetAttribute("Path")));
                             break;
                         case "DefaultFolder":
                             DefaultForlder = reader.ReadString();
                             break;
                     }
                 }
             }
         }
     }

     public class UpdateInfo
     {
         public UpdateInfo() { }

         public UpdateInfo(string filename, VersionType versionType, string version, string path)
         {
             FileName = filename;
             VersionType = versionType;
             Version = version;
             Path = path;
         }
         public string FileName;
         [XmlIgnore]
         public string Path;
         public VersionType VersionType;
         public string Version;
     }

     public enum VersionType
     {
         FileVersion,
         MD5
     }

 

注意下其中UpdateInfo多了一个Path属性，表示文件的实际路径，不需要显示给客户端，因此加了XmlIgnore标记。

在服务端需要配置UpdateInfoSection项和UpdateServiceHandler的地址映射。

在<system.web>节<httpHandlers>下添加一项：

     <httpHandlers>
       <add verb="*" path="update.aspx" type="MyService.UpdateServiceHandler"/>
     </httpHandlers>

其中MyService.UpdateServiceHandler需要替换为UpdateServiceHandler的完整名称。

然后添加UpdateInfoSection项：

   <configSections>
     <section name="ClientUpdateInfo" type="MyService.UpdateInfoSection"/>
   </configSections>

   <ClientUpdateInfo>
     <DefaultFolder>bin</DefaultFolder>
     <File FileName ="log4net.dll"/>
     <File FileName ="Castle.Core.dll"/>
     <File FileName ="Castle.DynamicProxy2.dll"/>
     <File FileName ="Client.dll" Path ="bin/Client.exe" />
     <File FileName ="client.config" VersionType="MD5"/>
   </ClientUpdateInfo>

DefaultFolder是在没有为文件提供Path时默认的包含文件的目录，配置比较简单。

好了，现在可以打开update.aspx页面看到文件的版本信息

在update.aspx后加上参数的话，例如?download=log4net.dll，就可以下载文件了。

 

最后，客户端只需要更新并运行程序就可以了，当然还需要设置一下服务端的地址（Properties.Settings.Default.Server）：

  static class Program
     {
         /// <summary>
         /// The main entry point for the application.
         /// </summary>
         [STAThread]
         static void Main()
         {
             UpdateHelper.Update();

             AppDomain domain = AppDomain.CreateDomain("client");
             domain.SetData("APP_CONFIG_FILE", "client.config");
             domain.ExecuteAssembly("Client.dll", AppDomain.CurrentDomain.Evidence, Environment.GetCommandLineArgs());
         }
     }