c++ 中 std::bind 的使用 

 1 #include <iostream>
 2 #include <functional>
 3 #include <string>
 4 void printTemperature(std::string& name, int daySeq, float temperature) {
 5     std::cout<< "name: " << name << std::endl;
 6 　  std::cout<< "daySeq: " << daySeq << std::endl;
 7     std::cout<< "temperature: " << temperature << std::endl;
 8 }
 9 
10 class Car {
11  public:
12     Car() : m_Color("red") {
13         
14     }
15     void print() {
16         std::cout << m_Color << std::endl;
17     }
18     std::string m_Color;
19 };
20 
21 int main()
22 {
23     // 去掉默认参数，std::placeholders::_2 表示printTemperature的第三个参数放在bindFunc1的第二个位置
24     std::string name = "A";
25     std::function<void(std::string&, float)> bindFunc1 = std::bind(printTemperature, std::placeholders::_1, 1, std::placeholders::_2);
26     bindFunc1(name, 100.1);
27     std::cout << "=================================" << std::endl;
28     
29     // 调整参数顺序
30     name = "B";
31     std::function<void(float,std::string&, int)> bindFunc2 = std::bind(printTemperature, std::placeholders::_2, std::placeholders::_3, std::placeholders::_1);
32     bindFunc2(3000.0, name, 2);
33     
34     // 调整参数顺序 和 去掉默认参数
35     name = "C";
36     std::function<void(int, std::string&)> bindFunc3 = std::bind(printTemperature, std::placeholders::_2, std::placeholders::_1, 100.1);
37     bindFunc3(10, name);
38     std::cout << "=================================" << std::endl;
39     
40     Car car;
41     // 需要显示获取成员函数的地址，因为编译器不会将对象的成员函数隐式转换为函数指针， &Car::print
42     std::function<void(void)>bindClassFunc = std::bind(&Car::print, &car);
43     bindClassFunc();
44     return 0;
45 }

 

posted @ 2022-07-20 20:57  海228  阅读(112)  评论(0)    收藏  举报