NullReferenceException When calling class function c#

Question

When I try to call this function I get NullreferenceException, if the code looks weird thats because I'm translating from c++ to c#.

public class MyPlayer_t
{
    int pLocal;
    public int Team;
    public int Health;
    public float[] Position = new float[3];

    public void ReadInformation()
    {
        pLocal = Mem.ReadInt(Client + playerBase);
        Team = Mem.ReadInt(pLocal + teamOffset);
        Health = Mem.ReadInt(pLocal + healthOffset);
        for (int i = 0; i < 3; i++)
        {
            Position[i] = Mem.ReadFloat(pLocal + Pos);
        }
    }
}

MyPlayer_t MyPlayer;

// This is how I call it
MyPlayer.ReadInformation();

Answer 1

You have to make object/instance of class using new keyword:

 MyPlayer_t MyPlayer = new MyPlayer_t();
 MyPlayer.ReadInformation();

Here is MSDN Reference to learn about the classes in C#.

Answer 2

Try and create an instance, and then call it.

var player = new MyPlayer_t();
player.ReadInformation();

If you wanted to actually call it as you've suggested, the class would need to be static, see the following C# static vs instance methods

Answer 3

This is reasonable. You have at first create an instance of the class. Like below:

MyPlayer_t myPlayer = new MyPlayer_t();

Then you can call it's method called ReadInformation like below:

myPlayer.ReadInformation();

The reason why you were getting this error was the fact that this line of code

MyPlayer_t MyPlayer;

creates a variable that can hold an object of type called MyPlayer_t. Since you don't assign to this variable a value, it gets it's default value, which is null. Then you try to call a method called ReadInformation on the the type that is stored in variable called MyPlayer. However, since MyPlayer is null you get this exception.