Question

Ok so I’m attempting to create a high score system and am using an array of a class within an object, however the error in the title appears which tells me that for some reason my objects are full of null variables, here are my classes:

class HighScores
{
    public HighScore[] MyScores = new HighScore[5];

    protected bool failedRead = false;

    private void SortHighScores(string NewName, int NewScore)
    {
        HighScore[] TmpScores = new HighScore[6];

        for (int i = 0; i < 5; i++)
        {
            TmpScores[i].Name = MyScores[i].Name; // Error Occurs here for `MyScores[i].Name` however in output box both MyScores and TmpScores show null
            TmpScores[i].Score = MyScores[i].Score;
        }
        TmpScores[5].Name = NewName;
        TmpScores[5].Score = NewScore;

        Array.Sort(TmpScores, delegate(HighScore x, HighScore y) { return x.Score.CompareTo(y.Score); });
        Array.Reverse(TmpScores);

        MyScores = new HighScore[5];
        for (int i = 0; i < 5; i++)
        {
            MyScores[i].Name = TmpScores[i].Name;
            MyScores[i].Score = TmpScores[i].Score;
        }
    }
}

class HighScore
{
    public string Name = "hello world";
    public int Score = 0;
}

And here is where I initialise an object of HighScores:

HighScores GameScores;
protected override void Initialize()
{
    base.Initialize();
    GameScores = new Highscores();
}

Surely the objects shouldn’t be null if I made them as new?

[EDIT]

OK so I’ve made a new function within the class HighScores to initialise the MyScores objects as new HighScore objects:

public void InitScores()
{
    for (int i = 0; i < 5; i++)
    {
        MyScores[i] = new HighScore();
    }
}

Which is called within protected override void Initialize() (I’m sure you’re all familiar with it, it’s standard in XNA). I also have added the same code in the class function: GameScores.SortHighScores to initialise TmpScores.

Still the same error, still the same place where it occurs, any ideas?

Answer 1

It looks like you need to create the instances of HighScore for your MyScores array. You only create the array in the code above.

So somewhere in the code you need code similar to

MyScores[i] = new HighScore();