建立 stdthread

在 C++中，使用 std::thread 類建立執行緒。執行緒是一個單獨的執行流程; 它類似於讓你的幫助者在你同時執行另一個任務時執行一項任務。當執行緒中的所有程式碼都被執行時，它就會終止。建立執行緒時，需要傳遞要在其上執行的內容。你可以傳遞給執行緒的一些事情：

• 免費功能
• 會員職能
• Functor 物件
• Lambda 表示式

自由函式示例 - 在單獨的執行緒上執行函式（ 例項 ）：

#include <iostream>
#include <thread>
 
void foo(int a)
{
    std::cout << a << '\n';
}
 
int main()
{
    // Create and execute the thread
    std::thread thread(foo, 10); // foo is the function to execute, 10 is the
                                 // argument to pass to it
 
    // Keep going; the thread is executed separately
 
    // Wait for the thread to finish; we stay here until it is done
    thread.join();
 
    return 0;
}

成員函式示例 - 在單獨的執行緒上執行成員函式（ 例項 ）：

#include <iostream>
#include <thread>
 
class Bar
{
public:
    void foo(int a)
    {
        std::cout << a << '\n';
    }
};
 
int main()
{
    Bar bar;
    
    // Create and execute the thread
    std::thread thread(&Bar::foo, &bar, 10); // Pass 10 to member function
 
    // The member function will be executed in a separate thread
 
    // Wait for the thread to finish, this is a blocking operation
    thread.join();
 
    return 0;
}

Functor 物件示例（ 例項 ）：

#include <iostream>
#include <thread>
 
class Bar
{
public:
    void operator()(int a)
    {
        std::cout << a << '\n';
    }
};
 
int main()
{
    Bar bar;
    
    // Create and execute the thread
    std::thread thread(bar, 10); // Pass 10 to functor object
 
    // The functor object will be executed in a separate thread
 
    // Wait for the thread to finish, this is a blocking operation
    thread.join();
 
    return 0;
}

Lambda 表示式示例（ 例項 ）：

#include <iostream>
#include <thread>
 
int main()
{
    auto lambda = [](int a) { std::cout << a << '\n'; };

    // Create and execute the thread
    std::thread thread(lambda, 10); // Pass 10 to the lambda expression
 
    // The lambda expression will be executed in a separate thread
 
    // Wait for the thread to finish, this is a blocking operation
    thread.join();
 
    return 0;
}