以下代码旨在通过线程中的套接字读取数据。
//main method from dll
function GetSocketData(const IP, Port: PChar): PChar; export; cdecl;
var
Thread: TMyThread;
DataIsRead: TEvent;
begin
DataIsRead := TEvent.Create(nil, True, False, '');
Thread:= TMyThread.Create(DataIsRead, IP, Port);
DataIsRead.WaitFor(INFINITE);
Result := BlockAlloc(Thread.ResultData);
DataIsRead.Free;
Thread.Free;
end;
TMyThreadBase = class(TThread)
protected
FResultData: string;
public
constructor Create;
property ResultData: string read FResultData;
end;
constructor TMyThreadBase.Create;
begin
inherited Create(False); // Suspended
FResultData := '';
FreeOnTerminate := False;
end;
TMyThread = class(TMyThreadBase)
private
FMyData: TMyData;
FSocketCom: TSocketCom;
//other params
protected
procedure Connect(Sender: TObject);
procedure Execute; override;
public
constructor Create(DataIsRead: TEvent; const IP, Port: PChar);
destructor Destroy; override;
end;
constructor TMyThread.Create(const IP, Port: PChar);
begin
inherited Create;
/init params/
CoInitialize(nil);
FSocketCom := ComCreate(FPort, FIP);
FSocketCom.OnConnect := Connect;//Connect method sends the special command to the port {`ClientSckt.Socket.SendBuf(B[0], Count)`}
FSocketCom.Reopen;
FMyData := TMyData.Create(DataIsRead, FSocketCom);//class used for received data interpretation
//DataIsRead event is being set when all data is interpreted
FSocketCom.SetRxFunc(FMyData.NCData);//set method for data interpretation
FMyData.InitData(...);//init values needed while data is being interpreted
end;
destructor TMyThread.Destroy;
begin
CoUninitialize;
inherited;
end;
procedure TMyThread.Execute;
begin
inherited;
while not Terminated do
Sleep(100);
//that is the place where I do not know what to do to wait while OnRead event is fired.
end;
TSocketCom = class(TCustomCom)
private
ClientSckt: TClientSocket;
procedure SocketConnect(Sender: TObject; Socket: TCustomWinSocket);
procedure SocketRead(Sender: TObject; Socket: TCustomWinSocket);
protected
procedure SetThread; override;
public
constructor Create;
destructor Destroy; override;
function Open:Boolean; override;
function Read( Buf:PAnsiChar; Size:Integer; Wait:Integer = 0 ):Integer; override;
end;
procedure TCustomCom.SetRxFunc(OnRxData: TRxDataEvent);
begin
...
SetThread;
...
end;
function TSocketCom.Open:boolean;
var
i,j:integer;
begin
...
ClientSckt:=TClientSocket.Create(nil);
ClientSckt.ClientType:=ctBlocking;
ClientSckt.HostAndAddress:='127.0.0.0';
ClientSckt.Port:=1234;
ClientSckt.OnConnect:=SocketConnect;
ClientSckt.Open;
...
end;
function TSocketCom.Read(Buf:PAnsiChar;Size:Integer; Wait:Integer):Integer;
begin
if Opened then
Result:=ClientSckt.Socket.ReceiveBuf(Buf^,Size);
if Result<0 then Result:=0;
end;
procedure TSocketCom.SetThread;
begin
inherited;
ClientSckt.OnRead:=SocketRead;
end;
问题:OnRead事件未被触发,虽然它接缝所有需要的实例都是在线程中创建的。建立连接并发送命令。
答案 0 :(得分:3)
这种代码是对线程的误用(以及对FreeOnTerminate
属性的误用),因为调用代码被阻塞等待线程终止,所以没有理由在线程中有一个线程第一名。
据说,默认情况下TClientSocket
以非阻塞模式运行,该模式在内部使用窗口消息来触发套接字事件。激活套接字的线程需要有一个消息循环,因此可以正确接收和分派这些套接字通知。否则,你必须在阻塞模式下使用套接字,正如Martin所说。
<强>更新强>
您显示的更新代码在多个级别上都是完全错误的。线程都是错的。 TClientSocket
用法完全错误。鉴于你的GetSocketData()
函数的阻塞特性,根本不需要在内部使用任何线程(特别是因为你声明GetSocketData()
本身是在一个线程中调用的,所以额外的线程是过度杀伤的) ,你根本不应该对TClientSocket
事件感到困扰,特别是OnRead
事件,特别是因为它根本不会在阻塞模式中被调用(这是你问题的根源!)。
你使代码变得更复杂,然后才需要。使用更像这样的东西:
function GetSocketData(const IP, Port: PChar): PChar; export; cdecl;
var
ClientSckt: TClientSocket;
//other params
begin
Result := nil;
try
/init params/
CoInitialize(nil);
try
ClientSckt := TClientSocket.Create(nil);
try
ClientSckt.ClientType := ctBlocking;
ClientSckt.HostAndAddress := IP;
ClientSckt.Port := Port;
ClientSckt.Open;
try
// send the special command to the port from here
// read all data and interpret from here
Result := BlockAlloc(...);
finally
ClientSckt.Close;
end;
finally
ClientSckt.Free;
end;
finally
CoUninitialize;
end;
except
end;
end;
答案 1 :(得分:0)
如果您想要所有客户&lt;&gt;服务器通信发生在这个函数和线程MyThreadForReading方法中,最简单的方法是在线程构造函数中构造一个TClientSocket实例(或者在Execute方法的顶部)。传递PChar,hostAddr,端口等作为构造函数参数。在构造函数/ execute中,使用参数,onRead事件加载TClientSocket并将clientType设置为'ctBlocking'。在执行中,将数据连接并循环读取到PChar中,直到它全部进入。当它进入时,你有一些选择通知主线程PChar缓冲区是“满”。我想PostMessage()可以触发主线程消息处理程序,但是如果你需要主线程等待,那么按照David的建议使用WaitFor()。