如何实现类的成员函数创建线程

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class CMySocket{  public:  DWORD WINAPI WorkThread(LPVOID CompletetionPortID);  ...};

  有如上类,在类中某函数想以函数(WorkThread)

  CreateThread(NULL, 0, WorkThread, &param, 0, &ThreadID))

  编译会报错:cannot convert parameter 3 from 'unsigned long (void *)' to 'unsigned long (__stdcall *)(void *)' None of the functions with this name in scope match the target type

  
解决方法:

  1.

  这种情况,一般是将线程函数申明为静态,如:

class CRealtimeTask{  public:  static UINT taskmain(LPVOID param);  BOOL StartTask();};

  在类中定义的成员函数,VC在编译时会强加一个this指针,所以才会出现上边的情况.将该成员函数声明为static类型,可以将this指针除去,但static成员函数只能访问static成员.

  

    2.

  以将线程函数申明成友员函数,这样可以传入该类的指针,访问类的成员; 

class CRealtimeTask{  public:  friend UINT taskmain(LPVOID param);  BOOL StartTask();};UINT taskmain(LPVOID param){  CRealtimeTask * pTaskMain = (CRealtimeTask *) param;  //通过pTaskMain指针引用.  return TRUE;}BOOL CRealtimeTask::StartTask(){  AfxBeginThread(taskmain,this);}


  3.

  可以对成员函数实现回调,并访问非静态成员的,如下所示,这是为了实现线程函数访问类成员而实现的类.比MFC的实现方法好象要好一点.

class base;typedef int (base::*fnCallBack)(void *p);struct callback(void *param;fnCallBack *pfuc;base *pThis;};class base{  static int myThreadfuc(void *p){  struct callback *p1=(struct callback *)p;  base *pthis=p1->base;fnCallBack *pfuc=p1->pfuc;void *param=p1->param;  int i=(pthis->*pfuc)(param);delete p;  return i;  }  public:  void myCreateThread(fnCallBack pfuc,void *param){  struct callback *p=new struct callback;  p.param=param;p.pThis=this;p.pfuc=pfuc;  ::CreateThread(myThreadfuc,p);  }  virtual int myCallBack(void *p){printf("It's base class./n");return 0;}};class derived: public base{  int myCallBack(void *p){printf("It's derived class/n");}};void myCreateThreadImitate(fnCallBack fuc,void *p){  (*fuc)(p);}void main(){  base p;char *param;  p.myCreateThread(&(base::myCallBack),param);  derived p2;p2.myCreateThread(&(base::myCallBack),param);}


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