std :: function and std :: bind

Transfer: https: //blog.csdn.net/shuilan0066/article/details/82788954

Example 1: Common Functions

void gFunc()

{

    cout << "gFunc" << endl;

}

int main ()

{

    std::function<void()> f = gFunc;

    f();

    getchar();

    return 0;

}

 

示例2 模板函数

template <class T>
T g_Add(T i, T j)
{
　　cout << i + j;
　　return i + j;
}


int main()
{
　　std::function<int(int,int)> f = g_Add<int>;
　　f(2,3);

　　getchar();
　　return 0;
}
 

 

Example Three: anonymous function 

Auto g_Lambda = [] ( int I, int J) 
{ 
　　return I + J; 
}; // anonymous functions here semicolon 

int main () 
{ 
　　STD :: function < int ( int , int ) > F = g_Lambda; 
　　COUT << F ( 2 , . 3 ); 

　　getchar (); 
　　return  0 ; 
}

 

Example Four: Object function

 / function object
 struct the Add 
{ 
　　int  operator () ( int I, int J) 
　　{ 
　　　　return I + J; 
　　} 
}; 

// template function object 
Template < class T>
 struct ADDT 
{ 
　　T operator () (T I, T J) 
　　{ 
　　　　return I + J; 
　　} 
}; 


int main () 
{ 
　　STD :: function < int ( int , int )> = F the Add (); 
　　COUT<<f(2,3)<<endl;

　　std::function<int(int, int)> ft = AddT<int>();
　　cout << ft(5, 6)<<endl;

　　getchar();
　　return 0;
}
 

 

Example 5: class member function 

class Computer 
{ 
　　public :
　　static  int the Add ( int I, int J) 
　　{ 
　　　　return I + J; 
　　} 

　　Template < class T>
　　static T ADDT (T I, T J) 
　　{ 
　　　　return I + J; 
　　} 

　　int ADDN ( int I, int J) 
　　{ 
　　　　return I + J; 
　　} 
}; 

// storing member function calls 

int main () 
{ 
　　// . 1, class static function
　　:: function STD < int ( int , int )> = F & Computer :: the Add; 
　　COUT << F ( . 1 , . 1 ) << endl; 

　　// 2, class static template function 
　　STD :: function < int ( int , int )>. ft :: = & Computer ADDT < int > ; 
　　COUT <<. ft ( . 1 , . 1 ) << endl; 



　　// common function to bind to the class object need to construct 
　　Computer C; 

　　// . 3, need to use common functions bind, to address & c class object bindings on 
　　STD :: function < int ( int , int)> = FN STD :: the bind (Computer & ADDN ::, & C, placeholders. 1 :: _, _ :: placeholders 2); 
　　COUT << fN ( . 1 , . 1 ) << endl; 

　　// . 4, normal function, may be such calls personally feel that the ratio bind trouble, do not recommend 
　　std :: function < int ( const Computer &, int , int )> = FN2 & Computer :: ADDn; 
　　cout << FN2 (c, 1 , 1 ) << endl; 

　　getchar (); 
　　return  0 ; 
}