2

我正在尝试将私有成员函数（不应作为公共或受保护的）调用为具有 Win32 函数的工作项QueueUserWorkItem()。我知道我以前做过，而且很容易，但现在我找不到那个片段，也不能让bind()伏都教工作。因此，就这个问题而言，该课程是：

class Arbitrary {

    public:
        Arbitrary() ;
        ~Arbitrary() ;

        bool    UsefulPublicFunction(unsigned uParameter) ;

    protected:

    private:
        void    PrivateWorkItem(void* pVoid) ;
} ;

在里面UsefulPublicFunction()我们可能会看到：

LPTHREAD_START_ROUTINE pThreadStartRoutine ;
ULONG uFlags = 0 ;
void* pContext = nullptr ;

if (QueueUserWorkItem(pThreadStartRoutine, pContext, uFlags)) {
    //blah blah blah
}

我似乎在杂草丛生的地方是分配给pThreadStartRoutine类似的东西：

pThreadStartRoutine = std::bind<&Arbitrary::PrivateWorkItem, this, std::placeholders::_1> ;

我认识到签名PrivateWorkItem可能应该更改为：

private:
    DWORD   WINAPI  PrivateWorkItem(void* pVoid) ;

即使有这种变化，也没有喜悦。VS2015 真的很讨厌我使用bind().

我的任务应该是什么pThreadStartRoutine样的？

4

2 回答 2

2

这似乎有效：

#include <Windows.h>

#include <stdio.h>

#include <functional>

using namespace std::placeholders;

class Arbitrary {

    public:

        bool UsefulPublicFunction(int uParameter);

    protected:

    private:
        typedef std::function<void (void)> CallbackType;
        static DWORD WINAPI ProcessWorkItem(void* pVoid);
        void PrivateWorkItem1(int arg1, int arg2);
        void PrivateWorkItem2(char * arg1);
};

void Arbitrary::PrivateWorkItem1(int arg1, int arg2)
{
    printf("Numbers are %u %u\n", arg1, arg2);
    return;
}

void Arbitrary::PrivateWorkItem2(char * arg1)
{
    printf("String is %s\n", arg1);
    return;
}

DWORD WINAPI Arbitrary::ProcessWorkItem(void* pVoid)
{
    CallbackType * callback = static_cast<CallbackType *>(pVoid);
    (*callback)();
    delete callback;
    return 0;
}

bool Arbitrary::UsefulPublicFunction(int param1)
{
    QueueUserWorkItem(&ProcessWorkItem, new CallbackType(std::bind(&Arbitrary::PrivateWorkItem1, this, param1, 7)), 0);

    QueueUserWorkItem(&ProcessWorkItem, new CallbackType(std::bind(&Arbitrary::PrivateWorkItem2, this, (char *)"This is my string")), 0);

    Sleep(1000);
    return true;
}

int main(int argc, char ** argv)
{
    Arbitrary x;

    x.UsefulPublicFunction(5);

    return 0;
}
于 2016-04-15T06:23:44.103 回答
1

尝试更多类似的东西：

class Arbitrary {

    public:
        Arbitrary() ;
        ~Arbitrary() ;

        bool UsefulPublicFunction(unsigned uParameter);

    protected:

    private:
        static DWORD WINAPI PrivateWorkItem(void* pVoid) ;
        void PrivateFunction();
} ;


DWORD WINAPI Arbitrary::PrivateWorkItem(void* pVoid)
{
    static_cast<Arbitrary*>(pVoid)->PrivateFunction();
    return 0;
}

...

if (QueueUserWorkItem(&PrivateWorkItem, this, 0)) {
    //blah blah blah
}
于 2016-04-14T22:34:21.260 回答