7.4: Structures in C++ (cont'd)
- Page ID
- 34674
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- Member functions inside structure: Structures in C cannot have member functions inside structure but Structures in C++ can have member functions along with data members.
- Direct Initialization: We cannot directly initialize structure data members in C but we can do it in C++.
// CPP program to initialize data member in c++
#include <iostream>
using namespace std;
struct Record {
int x = 7;
};
// Driver Program
int main()
{
Record s;
cout << s.x << endl;
return 0;
}
// Output
// 7
- Using struct keyword: In C, we need to use struct to declare a struct variable. In C++, struct is not necessary. For example, let there be a structure for Record. In C, we must use “struct Record” for Record variables. In C++, we need not use struct and using ‘Record‘ only would work.
- Static Members: C structures cannot have static members but is allowed in C++.
// C++ program with structure static member
struct Record {
static int x;
};
// Driver program
int main()
{
return 0;
}
- Constructor creation in structure: Structures in C cannot have constructor inside structure but Structures in C++ can have Constructor creation.
// C program to illustrate empty structure
#include <stdio.h>
// empty structure
struct Record {
};
- sizeof operator: This operator will generate 0 for an empty structure in C whereas 1 for an empty structure in C++.
// Driver program
int main()
{
struct Record s;
printf("%d\n", sizeof(s));
return 0;
}
Output in C++:
1
- Data Hiding: C structures do not allow concept of Data hiding but is permitted in C++ as C++ is an object oriented language whereas C is not.
- Access Modifiers: C structures do not have access modifiers as these modifiers are not supported by the language. C++ structures can have this concept as it is inbuilt in the language.
Adapted from: "Difference between C structures and C++ structures" by Gyanendra Singh Panwar is licensed under CC BY-SA 4.0