學習C#時,經常會遇到Web服務器功能的程序設計問題,這裏將介紹C#實現Web服務器功能的程序設計問題的解決方法。
C#實現Web服務器功能的程序設計
根據HTTP協議的作用原理,實現GET請求的Web服務器程序的方法如下:
創建TcpListener類對象,監聽某端口(任意輸入閒置端口 如:8080 )。等待、接受客戶機連接到該端口,得到與客戶機連接的socket;從與socket關聯的輸入流中讀取一行客戶機提交的請求信息,請求信息的格式爲:GET 路徑/文件名 HTTP/1.0。從請求信息中獲取請求類型。如果請求類型是GET,則從請求信息中獲取所訪問的HTML文件名。沒有HTML文件名時,則以index.html作爲文件名;
如果HTML文件存在,則打開HTML文件,把HTTP頭信息和HTML文件內容通過socket傳回給Web瀏覽器,然後關閉文件。否則發送錯誤信息給Web瀏覽器;關閉與相應Web瀏覽器連接的socket字。
C#實現Web服務器功能的代碼如下:
- using System;
- using System.IO;
- using System.Net;
- using System.Net.Sockets;
- using System.Text;
- using System.Threading ;
- class MyWebServer
- {
- private TcpListener myListener ;
- private int port = 8080 ; // 選者任何閒置端口
- //開始兼聽端口
- //同時啓動一個兼聽進程
- public MyWebServer()
- {
- try
- {
- //開始兼聽端口
- myListener = new TcpListener(port) ;
- myListener.Start();
- Console.WriteLine("Web Server Running... Press ^C to Stop...");
- //同時啓動一個兼聽進程 ''StartListen''
- Thread th = new Thread(new ThreadStart(StartListen));
- th.Start() ;
- }
- catch(Exception e)
- {
- Console.WriteLine("兼聽端口時發生錯誤 :" +e.ToString());
- }
- }
- public void SendHeader(string sHttpVersion, string sMIMEHeader,
int iTotBytes, string sStatusCode, ref Socket mySocket) - {
- String sBuffer = "";
- if (sMIMEHeader.Length == 0 )
- {
- sMIMEHeader = "text/html"; // 默認 text/html
- }
- sBuffersBuffer = sBuffer + sHttpVersion + sStatusCode + "\r\n";
- sBuffersBuffer = sBuffer + "Server: cx1193719-b\r\n";
- sBuffersBuffer = sBuffer + "Content-Type: " + sMIMEHeader + "\r\n";
- sBuffersBuffer = sBuffer + "Accept-Ranges: bytes\r\n";
- sBuffersBuffer = sBuffer + "Content-Length: " + iTotBytes + "\r\n\r\n";
- Byte[] bSendData = Encoding.ASCII.GetBytes(sBuffer);
- SendToBrowser( bSendData, ref mySocket);
- Console.WriteLine("Total Bytes : " + iTotBytes.ToString());
- }
- public void SendToBrowser(String sData, ref Socket mySocket)
- {
- SendToBrowser (Encoding.ASCII.GetBytes(sData), ref mySocket);
- }
- public void SendToBrowser(Byte[] bSendData, ref Socket mySocket)
- {
- int numBytes = 0;
- try
- {
- if (mySocket.Connected)
- {
- if (( numBytes = mySocket.Send(bSendData, bSendData.Length,0)) == -1)
- Console.WriteLine("Socket Error cannot Send Packet");
- else
- {
- Console.WriteLine("No. of bytes send {0}" , numBytes);
- }
- }
- else
- Console.WriteLine("連接失敗....");
- }
- catch (Exception e)
- {
- Console.WriteLine("發生錯誤 : {0} ", e );
- }
- }
- public static void Main()
- {
- MyWebServer MWS = new MyWebServer();
- }
- public void StartListen()
- {
- int iStartPos = 0;
- String sRequest;
- String sDirName;
- String sRequestedFile;
- String sErrorMessage;
- String sLocalDir;
- String sMyWebServerRoot = "E:\\MyWebServerRoot\\"; //設置你的虛擬目錄
- String sPhysicalFilePath = "";
- String sFormattedMessage = "";
- String sResponse = "";
- while(true)
- {
- //接受新連接
- Socket mySocket = myListener.AcceptSocket() ;
- Console.WriteLine ("Socket Type " +mySocket.SocketType );
- if(mySocket.Connected)
- {
- Console.WriteLine("\nClient Connected!!\n=\nCLient IP {0}\n",mySocket.RemoteEndPoint) ;
- Byte[] bReceive = new Byte[1024] ;
- int i = mySocket.Receive(bReceive,bReceive.Length,0) ;
- //轉換成字符串類型
- string sBuffer = Encoding.ASCII.GetString(bReceive);
- //只處理"get"請求類型
- if (sBuffer.Substring(0,3) != "GET" )
- {
- Console.WriteLine("只處理get請求類型..");
- mySocket.Close();
- return;
- }
- // 查找 "HTTP" 的位置
- iStartPos = sBuffer.IndexOf("HTTP",1);
- string sHttpVersion = sBuffer.Substring(iStartPos,8);
- // 得到請求類型和文件目錄文件名
- sRequest = sBuffer.Substring(0,iStartPos - 1);
- sRequest.Replace("\\","/");
- //如果結尾不是文件名也不是以"/"結尾則加"/"
- if ((sRequest.IndexOf(".") <1) && (!sRequest.EndsWith("/")))
- {
- sRequestsRequest = sRequest + "/";
- }
- //得帶請求文件名
- iStartPos = sRequest.LastIndexOf("/") + 1;
- sRequestsRequestedFile = sRequest.Substring(iStartPos);
- //得到請求文件目錄
- sDirName = sRequest.Substring(sRequest.IndexOf("/"), sRequest.LastIndexOf("/")-3);
- //獲取虛擬目錄物理路徑
- sLocalDir = sMyWebServerRoot;
- Console.WriteLine("請求文件目錄 : " + sLocalDir);
- if (sLocalDir.Length == 0 )
- {
- sErrorMessage = "<H2>Error!! Requested Directory does not exists</H2><Br>";
- SendHeader(sHttpVersion, "", sErrorMessage.Length, " 404 Not Found", ref mySocket);
- SendToBrowser(sErrorMessage, ref mySocket);
- mySocket.Close();
- continue;
- }
- if (sRequestedFile.Length == 0 )
- {
- // 取得請求文件名
- sRequestedFile = "index.html";
- }
- String sMimeType = "text/html";
- sPhysicalFilePath = sLocalDir + sRequestedFile;
- Console.WriteLine("請求文件: " + sPhysicalFilePath);
- if (File.Exists(sPhysicalFilePath) == false)
- {
- sErrorMessage = "<H2>404 Error! File Does Not Exists...</H2>";
- SendHeader(sHttpVersion, "", sErrorMessage.Length, " 404 Not Found", ref mySocket);
- SendToBrowser( sErrorMessage, ref mySocket);
- Console.WriteLine(sFormattedMessage);
- }
- else
- {
- int iTotBytes=0;
- sResponse ="";
- FileStream fs = new FileStream(sPhysicalFilePath,
FileMode.Open, FileAccess.Read, FileShare.Read); - BinaryReader reader = new BinaryReader(fs);
- byte[] bytes = new byte[fs.Length];
- int read;
- while((read = reader.Read(bytes, 0, bytes.Length)) != 0)
- {
- sResponsesResponse = sResponse + Encoding.ASCII.GetString(bytes,0,read);
- iTotBytesiTotBytes = iTotBytes + read;
- }
- reader.Close();
- fs.Close();
- SendHeader(sHttpVersion, sMimeType, iTotBytes, " 200 OK", ref mySocket);
- SendToBrowser(bytes, ref mySocket);
- //mySocket.Send(bytes, bytes.Length,0);
- }
- mySocket.Close();
- }
- }
- }
- }
- }