怎么做下载？

Question

procedure DownloadFile(strHost, strRemoteFileName, strLocalFileName: string; ClientSocket: TClientSocket);
var
  intReturnCode: Integer;
  s: string;
  szBuffer: array[0..128] of Char;
  FileOut: TFileStream;
begin
  if strRemoteFileName[1] <> '/' then
    strRemoteFileName := '/' + strRemoteFileName;
  FileOut := TFileStream.Create(strLocalFileName, fmCreate);
  try
    with ClientSocket do
    begin
      Host := strHost;
      ClientType := ctBlocking;
      Port := 80;
      try
        Open;
        s := 'GET ' + strRemoteFileName + '   HTTP/1.0'#13#10 +
             'Host: ' + strHost + #13#10#13#10;
        intReturnCode := Socket.SendBuf(Pointer(s)^, Length(s));
        if intReturnCode > 0 then
        begin
          while (intReturnCode > 0) do
          begin
            FillChar(szBuffer, SizeOf(szBuffer), 0);
            intReturnCode := Socket.ReceiveBuf(szBuffer, SizeOf(szBuffer));
            if intReturnCode > 0 then
              FileOut.Write(szBuffer, intReturnCode);
          end
        end
        else
          MessageDlg('No answer from server', mtError, [mbOk], 0);
        Close;
      except
        MessageDlg('No connection', mtError, [mbOk], 0);
      end;
    end;
  finally
    FileOut.Free
  end;
end;调用例子: procedure TForm1.Button1Click(Sender: TObject);
begin
  DownloadFile('www.scalabium.com', '/forums.htm', 'd:\forums.htm', ClientSocket1);
end;

Answer 1

delphi中的nmftp控件中Download函数可以下载文件，我给你一个
下载整个目录的例子：
function tftp.ex_download(remote_dir,local_dir:string):boolean;
var
    i,j,count1:integer;
    att,ss:string;
    current_dir:string;
    temp_dir:string;
begin
    try begin
        NMFTP1.ChangeDir(remote_dir);
        current_dir:=remote_dir;
        temp_dir:=copy(current_dir,2,length(current_dir));
        if not DirectoryExists(local_dir) then CreateDir(local_dir);
        if not directoryexists(local_dir+temp_dir) then createdir(local_dir+temp_dir);
        nmftp1.ParseList:=true;
        NMftp1.list;
        count1:=nmftp1.FTPDirectoryList.name.Count;
        for i:=0 to count1-1  do begin
            file://必须
            NMFTP1.ChangeDir(current_dir);
            nmftp1.list;
            ss:=nmftp1.FTPDirectoryList.name.Strings[i];
            att:=nmftp1.FTPDirectoryList.Attribute.Strings[i];
            if (copy(pchar(att),1,1)<>'d')and(copy(pchar(att),1,1)<>'D') then begin
                if not DirectoryExists(local_dir) then CreateDir(local_dir);
                NMFTP1.Download(current_dir+ss,local_dir+temp_dir+ss);
            end
            else begin
                if not directoryexists(local_dir+temp_dir+ss) then createdir(local_dir+temp_dir+ss);
                file://递归调用
                ex_download(remote_dir+ss+'\',local_dir);
            end;
        end;
           result:=true;
    end
    except
    On E:Exception do begin
        result:=false;
    end;
    end;
end;

Answer 2

这些下载的例子对服务器有没有特别的要求呢？能不能吧下载的大概思想讲一下？还有怎么自动定位一个URL资源？