Removing the const-ness (constant-ness) of the 'this' pointer in C++

Compiler: Visual C++ Express Edition 2005

Compiled on Platform: Windows XP Pro SP2

Header file: Standard

Additional project setting: Set project to be compiled as C++

Project -> your_project_name Properties -> Configuration Properties -> C/C++ -> Advanced -> Compiled As: Compiled as C++ Code (/TP)

Other info:

To do: Removing the constant-ness of the this pointer that point to an object in C++

To show: How to remove the const-ness of the 'this' pointer in C++ programming

// Removing the const-ness of the 'this' pointer

#include <iostream>

using namespace std;

class Test

{

public:

void GetNumber(int);

// Read only function...

void DisplayNumber() const;

private:

int Number;

};

void Test::GetNumber(int Num)

{Number = Num;}

void Test::DisplayNumber() const

{

cout<<"\nBefore removing const-ness: "<<Number;

const_cast<Test>(this)->Number+=2;

cout<<"\nAfter removing const-ness: "<<Number<<endl;

}

int main(void)

{

Test p;

p.GetNumber(20);

p.DisplayNumber();

return 0;

}

Output example:

Before removing const-ness: 20

After removing const-ness: 22

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