用API函数实现简单的网络发送和接收

unit Unit1;interfaceuses   Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,     Dialogs,winsock, StdCtrls, ExtCtrls, DB, ADODB;type   TForm1 = class(TForm)     edtHostIP: TEdit;     edtHostPort: TEdit;     btnSend: TButton;     lstTags: TListBox;     Timer1: TTimer;     lblMsg: TLabel;     conn: TADOConnection;     cmd: TADOCommand;     lstSTag: TListBox;     lstTagValue: TListBox;     lstRecv: TListBox;     procedure FormCreate(Sender: TObject);     procedure ConnectHost;     procedure GetData(myStr:string);     procedure msg(myStr:string);     procedure FormDestroy(Sender: TObject);     procedure btnSendClick(Sender: TObject);     procedure Timer1Timer(Sender: TObject);     procedure SaveToDB;   private     { Private declarations }   public     { Public declarations }   end;var   Form1: TForm1;   skt:TSOCKET;   addr:TSockAddr;implementation{$R *.dfm}procedure TForm1.ConnectHost;var   re:integer;begin   skt:=socket(AF_INET,SOCK_STREAM,0);   if skt=INVALID_SOCKET then     begin       msg('create socket failed!');       exit;     end   else     msg('create socket ok');   ZeroMemory(@addr,sizeof(addr));   addr.sin_family:=AF_INET;   addr.sin_addr.S_addr:=inet_addr(pchar(edtHostIP.text));   addr.sin_port:=htons(strtoint(edtHostPort.Text));   re:=connect(skt,addr,sizeof(addr));   if re<>0 then     begin       msg('connect host '+edtHostIp.Text+' failed!');       exit;     end   else     msg('connect host '+edtHostIp.Text+' ok');end;procedure TForm1.FormCreate(Sender: TObject);var   WSAData:TWSAData;begin   lstTags.Items.LoadFromFile('lics.txt');   if (WSAStartup(makeword(1,0),WSAData)<>0) then     begin       msg('Initialize WinSock failed!');       exit;     end   else     msg('Initialize winsock   ok');end;procedure TForm1.msg(myStr: string);begin   lblmsg.Caption:=myStr;end;procedure TForm1.FormDestroy(Sender: TObject);begin   WSACleanUp;end;procedure TForm1.GetData(myStr: string);var   BufSend,BufRecv:pchar;   re:integer;begin   getMem(BufSend,1024);   ZeroMemory(BufSend,1024);   myStr:=myStr+#10;   StrPCopy(BufSend,myStr);   re:=send(skt,BufSend^,length(BufSend),0);   if re=SOCKET_ERROR then     msg('send error');   GetMem(BufRecv,1024);   ZeroMemory(BufRecv,1024);   recv(skt,BufRecv^,1024,0);   lstTagValue.Items.Add(trim(copy(strpas(BufRecv),14,length(strpas(BufRecv)))));   lstRecv.Items.Add(strpas(BufRecv));   FreeMem(BufSend);   FreeMem(BufREcv);end;procedure TForm1.btnSendClick(Sender: TObject);var   i,iPos:integer;   s:string;   s1,s2,s3:string;begin   msg('receive remote data ......');   connectHost;   lstRecv.Clear;   lstSTag.Clear;   lstTagValue.Clear;   for i:=0 to lstTags.Count-1 do     begin       application.ProcessMessages;       s:=lstTags.Items[i];         // crac_bat11.cpv       s1:=copy(s,6,length(s)-4);   // bat11.cpv       iPos:=pos('.',s);       s2:='G01 FG 01 '+s1;         //   G01 FG 01 BAT11.CPV       s3:=copy(s,1,iPos-1);        // CRAC_BAT11       lstSTag.Items.Add(s3);       try         GetData(s2);       except         msg('error reading remote date... you should retry!');       end;     end;   msg('End at :'+datetimetostr(now()));   closesocket(skt);   SaveToDB;   msg('Save to infoplus end now :'+datetimetostr(now()));end;procedure TForm1.Timer1Timer(Sender: TObject);begin   btnSendClick(sender);end;//±£´æÊý¾Ýµ½Êý¾Ý¿âÖÐprocedure TForm1.SaveToDB;var   i:integer;   sTag,SVal,sSQL:string;begin   try     conn.Open();     msg('connect database server OK');   except     msg('connect database server failed');     exit;   end;//   lstSQL.Clear;   for i:=0 to lstSTag.Count-1 do     begin       sTag:=lstSTag.Items[i];       sVal:=lstTagValue.Items[i];       if (sVal<>'62') AND (sVal<>'61') then         begin           sSQL:='update ip_analogdef set ip_input_value='+sVal+' where name=''+sTag+'';           //sSQL:='update ip_analogdef set ip_input_value='+sVal+' where name=''+sTag+'';           try           cmd.CommandText:=sSQL;           cmd.Execute;           except           msg('error:update failed!');           conn.Close;           end;         end;//       lstSQL.Items.Add(sSQL);     end;   conn.Close;end;end.