Some forced type conversions in C + +

In C language, some forced type conversions are often seen, mainly in front of variable names (types). In C + +, there are some differences with C language, there are four types of forced type conversion in C + +.

1. Static_cast Its main transformation is the conversion between the relevant types

   
   

   int main ()

   {

   float a = 1.2;

   int B = static_cast<int> (a);

   cout << b << Endl;

   GetChar ();

   return 0;

   }

2.reinterpret_cast Its main transformation is the conversion between unrelated types

int main ()

{

int a = 1;

int *p = &a;

int b = reinterpret_cast<int> (p);

cout << b << Endl;

GetChar ();

return 0;

}

3.const_cast is a variable that unlocks the const type so that it can change the value of the variable

int main ()

{

volatile const int a = 1;

int *p = Const_cast<int *> (&a);

*p = 2;

cout << a << Endl;

GetChar ();

return 0;

}

4.dynamic_cast is a dynamic transformation, it mainly functions: 1. Can only be used for classes containing virtual functions 2. First check whether the conversion is successful, if the conversion is successful, if not return 0

Class A

{

Public

int _a;

virtual void Show ()

{}

};

Class B:p ublic A

{

Public

int _b;

};

void Test ()

{

A;

b b;

B *PB =dynamic_cast<b *> (&a);

cout << PB << Endl;

}

int main ()

{

Test ();

GetChar ();

return 0;

}

Some forced type conversions in C + +