相信衆多的 TCP 網絡服務器，均是由 TIdTCPServer 來提供服務，我的《網絡存儲服務器》也是。
即然是TCP服務器，若是需要相應的客戶端來支持，那麼，由這個服務端口(TCP)直接來提供客戶端安裝程序 WEB 下載是不是變得很方便？再也不用另加一個TIdHTTPServer來做了, 當然，若是需要提供 WEB 管理，還得麻煩他老人家。
HTTP協議：
在 IE 由 http://127.0.0.1:3001 連接到這個端口(Port=3001)時，發過來以下內容：
GET / HTTP/1.1Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*Accept-Language: zh-cnAccept-Encoding: gzip, deflateUser-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322)Host: 127.0.0.1:3001Connection: Keep-AliveCookie: iscookies=0只有第一行纔是我所需要的並且是有用的，後面的可省略，假定下載的客戶端安裝程序文件名是 ClientSetup.exe, 此時提供下載時，IE 會有不知道是什麼文件的麻煩，因此必須將客戶端IE地址改成 http://127.0.0.1:3001/ClientSetup.exe 他才能知道是什麼文件與文件名，通常是採用JAVA網頁轉向技術（見後面的代碼）。
GET /ClientSetup.exe HTTP/1.1...... 下面的省略其他服務器應迴應 IE 的內容，見下面:
// TIdTCPServer * IdTcpServer 的 OnExecute 事件處理函數void __fastcall TForm1::IdTCPServerExecute(TIdContext *AContext)
{
AnsiString ReadLn; TIdIOHandler * IOHandler = AContext->Connection->IOHandler; try
{
while (IdTCPServer->Active) { ReadLn = IOHandler->ReadLn(); if (ReadLn.Length()) if (ReadLn.Pos("GET ") == 1) { ReadLn.SetLength(ReadLn.Pos(" HTTP/")-1); ReadLn.Delete(1, 4); // 刪除前面的 GET 與空格 while (IOHandler->ReadLn().Length()); // 讀取完後面的內容 if (!FileExixts("ClientSetup.exe")) { AnsiString HTML = "<HTML> <HEAD> "; HTML += "<script LANGUAGE="JavaScript"> "; HTML += "function closeit() {"; HTML += "setTimeout("self.close()",10000)"; // HTML += "} "; HTML += "closeit()"; HTML += "</script> "; HTML += "</HEAD> "; HTML += "<BODY>客戶端安裝程序不存在,正在關閉窗口...</BODY> "; HTML += "</HTML>"; ReadLn = "HTTP/1.1 200 OK "; ReadLn += "Server: Goldray Network Storage Server 2.0 "; ReadLn += "Date: " + DateTimeToHTTPFormat(Now()) + " "; ReadLn += "Content-Length: " + IntToStr(HTML.Length()) + " "; ReadLn += "Content-Type: text/html "; ReadLn += "Expires: " + DateTimeToHTTPFormat(Now()) + " "; ReadLn += "Set-Cookie: path=/ "; ReadLn += "Cache-control: no-cache"; IOHandler->WriteLn(ReadLn); IOHandler->WriteLn(); Sleep(100); IOHandler->WriteLn(HTML); IOHandler->WriteLn();
} else if (ReadLn.UpperCase() == "/CLIENTSETUP.EXE") { ReadLn = "HTTP/1.1 200 OK "; ReadLn += "Server: Goldray Network Storage Server 2.0 "; ReadLn += "Date: " + DateTimeToHTTPFormat(Now()) + " "; ReadLn += "Content-Type: application/octet-stream "; ReadLn += "Accept-Ranges: bytes "; ReadLn += "Last-Modified: "; ReadLn += DateTimeToHTTPFormat(FileDateToDateTime(FileAge("ClientSetup.exe"))); ReadLn += " "; ReadLn += "Content-Length: " + IntToStr(FileGetSize("ClientSetup.exe")); IOHandler->WriteLn(ReadLn); // 發送HTTP前導 IOHandler->WriteLn(); IOHandler->WriteFile("ClientSetup.exe"); Sleep(100); AContext->Connection->Disconnect(); // 斷開吧，已經不需要了 break; } else // 若 IE 不是 http://......./ClientSetup.exe 讀取的，總是轉向這裏 { AnsiString HTML = "<HTML> <HEAD> "; HTML += "<script LANGUAGE="JavaScript"> "; HTML += "<!-- "; HTML += "window.location="http://"; HTML += AContext->Binding()->IP + ":"; HTML += IntToStr(AContext->Binding()->Port) + "/ClientSetup.exe" "; HTML += "// --> "; HTML += "</script> "; HTML += "</HEAD> "; HTML += "<BODY>正在轉向客戶端下載,請稍候...</BODY> "; HTML += "</HTML>"; ReadLn = "HTTP/1.1 200 OK "; ReadLn += "Server: Goldray Network Storage Server 2.0 "; ReadLn += "Date: " + DateTimeToHTTPFormat(Now()) + " "; ReadLn += "Content-Length: " + IntToStr(HTML.Length()) + " "; ReadLn += "Content-Type: text/html "; ReadLn += "Expires: " + DateTimeToHTTPFormat(Now()) + " "; ReadLn += "Set-Cookie: path=/ "; ReadLn += "Cache-control: no-cache"; IOHandler->WriteLn(ReadLn); IOHandler->WriteLn(); Sleep(100); IOHandler->WriteLn(HTML); IOHandler->WriteLn(); } } else { // ... 這裏纔是你的 TCP 服務器指令處理過程 } } } catch (...) { Sleep(100); }
}當然，實際使用時建議文件名使用含路徑的全稱, 使用變量是不錯的選擇。
哦，還小了兩個函數，一併附上:
// HTML 迴應時間必須是 GMT 格式AnsiString DateTimeToHTTPFormat(TDateTime ADateTime){ TSystemTime GMTTime; TFileTime DT; DateTimeToSystemTime(ADateTime, GMTTime); SystemTimeToFileTime(&GMTTime, &DT); LocalFileTimeToFileTime(&DT, &DT); FileTimeToSystemTime(&DT, &GMTTime); AnsiString wdays[7] = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"}; AnsiString monthnames[12] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"}; AnsiString Result = wdays[GMTTime.wDayOfWeek]; Result += ", "; TVarRec argd[1] = {GMTTime.wDay}; TVarRec args[4] = {GMTTime.wYear, GMTTime.wHour, GMTTime.wMinute, GMTTime.wSecond}; Result += Format("%.2d ", argd, 0); Result += monthnames[GMTTime.wMonth-1]; Result += Format(" %.4d %.2d:%.2d:%.2d", args, 3); Result += " GMT"; return Result;}下面的代碼，網上到處都是啦，也就來湊一下字數吧
// 取文件大小#include <stdio.h>__int64 __fastcall FileGetSize(AnsiString AFileName){ __int64 fSize = 0; if (FileExists(AFileName)) { FILE * fp = fopen(AFileName.c_str(),"rb"); if(fp) { fseek(fp,0,SEEK_END); fSize = ftell(fp); fclose(fp); } } return fSize;}以上程序在 C++Builder 2006 + Indy10 下通過。