I want to create an array to store actual objects and not pointers to objects in C++?
Can somebody explain how do I do that? is it better to use vectors or just directly like:
Student s [10];
OR
Student s [10][];
3 Answers
Using:
Student s [10];
Creates an array of 10 Student instances.
I think that Student s [10][]; is invalid.
But with C++ I'd not use C type arrays, it's better to use classes like std::vector or C++0x std::array which may not be available with not up-to date standard libraries/compilers.
Example for the above with a std::vector
#include <vector>
...
std::vector<Student> students(10);
And with an std::array:
#include <array>
...
std::array<Student, 10> students;
6 Comments
Mohamad Ibrahim
thanks man I wanted to accept ur full answer but it doesn't allow me to do so :((
Mohamad Ibrahim
One more Q: how can I define Vector size in header file? can't I? How to redefine it then in the cc file?
Constantinius
A
std::vector has no fixed size, you can .push_back() elements into it (and remove them). You can retrieve the current size with .size().Mohamad Ibrahim
thnx but I have a known size of this vector.. Is it better fixing its size in advance?
Constantinius
If you type the size of the vector in its constructor like in the example above (
std::vector<Student> students(10);) it has this as its initial size. If you don't remove elements from or insert elements into the std::vector the size does not change and you can use your fixed size. But unfortunately you cannot fix the size of the vector to a certain amount, but this should not worry you. |
Don't use arrays. Arrays are C not c++. Use std::vector instead, which is the C++ way to handle this.
2 Comments
Mohamad Ibrahim
Can u suggest me a way to use Vectors to store actuall objects? thanks
Mooing Duck
@shaklasah: vectors always store actual objects unless you specifically tell them otherwise.
I would suggest using std::vector if you want to make your array growable, otherwise just use Student students[10]; for 10 objects.
[]is valid syntax.