c++ - 如何线程化作为类方法的可调用函数

Question

使用 MS VC++ 2012 和 Boost 库 1.51.0

这是我的问题的快照：

struct B {
    C* cPtr;
}

struct C {
    void callable (int);
}

void function (B* bPtr, int x) {
    // error [1] here
    boost::thread* thrPtr = new boost::thread(bPtr->cPtr->callable, x) 
    // error [2] here
    boost::thread* thrPtr = new boost::thread(&bPtr->cPtr->callable, x) 
}

[1] 错误 C3867: 'C::callable': 函数调用缺少参数列表；使用 '&C::callable' 创建指向成员的指针

[2] error C2276: '&' : 对绑定成员函数表达式的非法操作

Answer 1

你想要boost::thread* thrPtr = new boost::thread(&C::callable, bPtr->cPtr, x);。这是一个工作示例：

#include <sstream>
#include <boost/thread.hpp>
#include <boost/bind.hpp>


struct C {
    void callable (int j)
    { std::cout << "j = " << j << ", this = " << this << std::endl; }
};

struct B {
    C* cPtr;
};

int main(void)
{
    int x = 42;
    B* bPtr = new B;
    bPtr->cPtr = new C;

    std::cout << "cPtr = " << bPtr->cPtr << std::endl;;

    boost::thread* thrPtr = new boost::thread(&C::callable, bPtr->cPtr, x);
    thrPtr->join();
    delete thrPtr;
}

样本输出：

cPtr = 0x1a100f0
j = 42, this = 0x1a100f0