C++ Programming Code Examples
C++ > Pointers Code Examples
function chaining calls using this pointer
/* function chaining calls using this pointer
Another example of using this pointer is to return the reference of current object so that you can chain function calls, this way you can call all the functions for the current object in one go. Another important point to note in this program is that I have incremented the value of object's num in the second function and you can see in the output that it actually incremented the value that we have set in the first function call. This shows that the chaining is sequential and the changes made to the object's data members retains for further chaining calls. */
#include <iostream>
using namespace std;
class Demo {
private:
int num;
char ch;
public:
Demo &setNum(int num){
this->num =num;
return *this;
}
Demo &setCh(char ch){
this->num++;
this->ch =ch;
return *this;
}
void displayMyValues(){
cout<<num<<endl;
cout<<ch;
}
};
int main(){
Demo obj;
//Chaining calls
obj.setNum(100).setCh('A');
obj.displayMyValues();
return 0;
}
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