Chapter 14: Problem 20
Explain the programming steps necessary to make a class's member function static.
Short Answer
Expert verified
To create and use a static member function in a class, follow these steps:
1. Understand the purpose: Static member functions are class-level functions that don't depend on a class instance and can be called without creating an object of the class. These functions can access static data members and other static member functions but not non-static members.
2. Create a class: Define a class where you want to implement the static member function. For example:
```cpp
class Counter {
public:
Counter() {
count++;
}
private:
static int count;
};
```
3. Initialize the static data member: Ensure the static data member is initialized outside the class. In our case, initialize the `count` variable to 0.
```cpp
int Counter::count = 0;
```
4. Declare a static member function: Add the `static` keyword before the return type of the function in the class declaration.
```cpp
class Counter {
public:
Counter() {
count++;
}
static int getCount() {
return count;
}
private:
static int count;
};
```
5. Call the static member function: Call the static member function directly using the class name and scope resolution operator.
```cpp
#include
using namespace std;
int main() {
Counter c1;
Counter c2;
Counter c3;
cout << "Number of instances created: " << Counter::getCount() << endl;
return 0;
}
```
This example demonstrates the creation and use of static member functions in a class, resulting in the output:
```
Number of instances created: 3
```
Step by step solution
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