C++的int初始化

int MyInt(56);

 
std::cout<<"MyInt="<<MyInt<<std::endl;

 

 
 
int MySecondInt = int();        //int变量可以这样初始化

 
std::cout<<MySecondInt<<std::endl;

 

 
 

         //那么可不可以这样初始化呢? 

 

 int MyThirdInt(int());
 
    
  //error!!! now, this is exactly a function
 
        
 

 
所以 
 MyThirdInt 
 正确的写法是
 

 
int MyThirdInt(int())
 
 
{
 
 
        // other code...  
 
 
return 0;
 
 
}
 

 
既然MyThirdInt 是一个函数, 那么里面的参数是什么东东呢?
 

 
//我们在声明一个函数
 
 
 

  int OtherInt()
 
 
 

  {
 
 
 
return 33;
 
 
 

  }
 
 
 

  
 
 

  //再看三行代码
 
 
 

 
  

   int (*pfunc)();
  
 
  

   pfunc = OtherInt;
  
 
  

   std::cout<<"MyThirdInt is: "<<MyThirdInt(pfunc)<<std::endl;
  
 
 

  
 
MyThirdInt 的参数是个函数指针,但是函数指针好像不能取出来....
 

 
所以这个特殊的Int变量需要重新定义,就像下面这样:
 

 
 
 

  int MyThirdInt(int (*pInt)())
 
 
 

  {
 
 
 
return pInt();
  
 
 

  }
 
 
 

  
 
 

  ======================完整代码========================
 
 
 

  
 
 
// hellomsg.cpp : 
 
  
//
 
  

   
 
  
#include "stdafx.h"
 
  
#include <iostream>
 
  

   
 
  

   
 
  
int OtherInt()
 
  
{
 
  

   return 33;
 
  
}
 
  

   
 
  
int MyThirdInt(int (*pInt)())
 
  
{
 
  

   
 
  

   return pInt();
 
  
}
 
  

   
 
  
int _tmain(int argc, _TCHAR* argv[])
 
  
{
 
  

   int MyInt(56);
 
  

   std::cout<<"MyInt="<<MyInt<<std::endl;
 
  

   
 
  

   int MySecondInt = int();
 
  

   std::cout<<MySecondInt<<std::endl;
 
  

   
 
  

   int (*pfunc)();
 
  

   pfunc = OtherInt;
 
  

   std::cout<<"MyThirdInt is: "<<MyThirdInt(pfunc)<<std::endl;
 
  

   
 
  

   return 0;
 
  
}