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std :: thread成员函数。 应该通过该指针访问类字段吗?

[英]std::thread member function. Should class fields be accessed by this pointer?

Given a class such as: 给定一个类,例如:

class MyClass {
  private:
  vector<std::string> data;

  void threadWork(std::vector<std::string> *data_ptr) {
    // some thread work... e.g
    for(int i=0; i < data_ptr->size(); i++) {
       std::string next = (*data_ptr)[i];
       // do stuff
    }
  }

  void callThreadedFunc(int nthread) {
    std::vector<std::thread> tgroup;
    std::vector<std::string> data_ptr = &data;
    for(int i=0; i < nthreads; i++) {
     tgroup.push_back(std::thread(&myClass::threadWork, this, data_ptr));
    }
    for(auto &t : tgroup) {t.join();}
  }
}

this is required to be passed into the thread constructor. this需要传递给线程构造函数。 Does this mean I should be accessing all class fields that thread requires via this instead of by field specific pointers? 这是否意味着我应该通过this而不是通过特定于字段的指针来访问线程需要的所有类字段? For example, threadWork() should access data as follows: 例如, threadWork()应按以下方式访问data

void threadWork(MyClass *obj) {
// some thread work... e.g
  for(int i=0; i < obj->data.size(); i++) {
     std::string next = obj.data[i];
     // do stuff
  }
}

Since threadWork is a member function and you properly create the thread using this , you can access all member variables of the instance normally, no need to pass a pointer or reference to the data. 由于threadWork是成员函数,并且您可以使用this正确创建线程,因此您可以正常访问实例的所有成员变量,而无需传递指针或对数据的引用。

Doing just 只是做

std::thread(&myClass::threadWork, this)

is enough, and then in the thread function you can use the member variables normally: 足够,然后在线程函数中可以正常使用成员变量:

void threadWork(/* no argument */) {
    // some thread work... e.g
    for(int i=0; i < data.size(); i++) {
        std::string next = data[i];  // Uses the member variable "normally"
       // do stuff
    }
}

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