Initializing length of std::vector

[karnavor]

Hello,

I know that when writing a class declaration, if the class contains an array of fixed length, then the length of that array can be initialized in the class declaration, without having to do so in the constructor. For example :

class MyClass
{
    int my_array[100];
};

But, is it also possible to do this with an std::vector? For example :

class MyClass
{
    std::vector<int> my_vector(100);
};

Or can the length of std::vectors only be set in the class constructor?

Thanks

[Paul McKenzie]

But, is it also possible to do this with an std::vector? For example :

std::vector is no different than any C++ class. If it needs to be initialized on construction of the containing object, then you initialize it in the object's initialization list.

#include <vector>

class MyClass
{
    std::vector<int>  my_vector;
    public:
         MyClass() : my_vector(100) { }
};

Regards,

Paul McKenzie

[cilu]

And you can always use method resize() to change the number of the elements in the vector.

For a tutorial I recommend this: http://www.codeguru.com/cpp/cpp/cpp_...icle.php/c4027.