Does the use of Static Variables in C# hinder secure coding practices?

Question

I am new to C# programming and I am currently using many static variables in my code. Below is one example:

class Program
{
    public int I//Can be used to access the variable i anywhere from the code as it is public
    {
        get { return i; }
        set { i = value; }
    }

    static int i = 0; // A private static integer
    static void Main(string[] args)
    {
        i = 1;// The main function is changing this integer
    }

    void reset() { 
        i = 0;// another function is changing the value of integer i
    }
}

class otherclass 
{
    void otherreset()
    {
        Program program = new Program();
        program.I = 1;// another function in another class is changing the value of integer i(indirectly)   

    }

}

1. The static variable i is available to all the functions in that class.
2. Then there is I which shares i with every function in the code as it is public. - not sure if I should even be doing this.

I did find this thread about using static variables in C# but I'd like to know, if this is a standard practice from a security perspective. I am concerned that the variable resides in the same location in memory throughout the execution of the program.

Are there any other better ways in general to share a variable between various functions.

Answer 1

static int i = 0; // A private static integer

Here you declared a static member. So far so good.

static void Main(string[] args)
{
    int i = 1;// The main function is changing this integer
}

No, it doesn't. int i means you declared a new local variable named i.

void reset() { 
    int i = 0;// another function is changing the value of integer i
}

No, it doesn't. int i means you declared a new local variable named i.

I'd like to know if this is a standard practice from a security perspective.

No, it isn't, and no, it's not related to security. You should avoid using static members as much as possible. I think that the actual reasons why are, currently, way too far from your current level of knowledge and understanding. Just take it as a best practice.

I am concerned that the variable resides in the same location in memory throughout the execution of the program.

Well, a variable that would 'travel' between memory locations wouldn't be a good idea :-) Variables are, very simplistically put, named locations in memory.

are there any other better ways in general to share a variable between various functions.

Yes, start by learning about function parameters, member fields, and properties. Use whatever beginner C# book you have available, or search online.