Simpler / more efficient method of nested if ... else flow?

Question

I'm currently working on an emulation server for a flash-client based game, which has a "pets system", and I was wondering if there was a simpler way of going about checking the level of specified pets.

Current code:

public int Level
{
    get
    {
        if (Expirience > 100) // Level 2
        {
            if (Expirience > 200) // Level 3
            {
                if (Expirience > 400) // Level 4 - Unsure of Goal
                {
                    if (Expirience > 600) // Level 5 - Unsure of Goal
                    {
                        if (Expirience > 1000) // Level 6
                        {
                            if (Expirience > 1300) // Level 7
                            {
                                if (Expirience > 1800) // Level 8
                                {
                                    if (Expirience > 2400) // Level 9
                                    {
                                        if (Expirience > 3200) // Level 10
                                        {
                                            if (Expirience > 4300) // Level 11
                                            {
                                                if (Expirience > 7200) // Level 12 - Unsure of Goal
                                                {
                                                    if (Expirience > 8500) // Level 13 - Unsure of Goal
                                                    {
                                                        if (Expirience > 10100) // Level 14
                                                        {
                                                            if (Expirience > 13300) // Level 15
                                                            {
                                                                if (Expirience > 17500) // Level 16
                                                                {
                                                                    if (Expirience > 23000) // Level 17
                                                                    {
                                                                        return 17; // Bored
                                                                    }
                                                                    return 16;
                                                                }
                                                                return 15;
                                                            }
                                                            return 14;
                                                        }
                                                        return 13;
                                                    }
                                                    return 12;
                                                }
                                                return 11;
                                            }
                                            return 10;
                                        }
                                        return 9;
                                    }
                                    return 8;
                                }
                                return 7;
                            }
                            return 6;
                        }
                        return 5;
                    }
                    return 4;
                }
                return 3;
            }
            return 2;
        } 
        return 1;
    }
}

Yes, I'm aware I've misspelt Experience, I had made the mistake in a previous function and hadn't gotten around to updating everything.

Answer 1

Use a SortedList<int, int> and iterate over it until you find a value that is higher than the value you are searching for. You can do it using a simple iteration as in the answer you have already accepted. Or it can be done elegantly using LINQ (at a slight performance cost):

SortedList<int, int> levels = new SortedList<int, int>
    {
        {0, 1},
        {100, 2},
        {200, 3},
        {400, 4},
        {600, 5},
    };

public int Experience;
public int Level
{
    get
    {
        return levels.Last(kvp => Experience >= kvp.Key).Value;
    }
}

Note that storing the 'level' is actually not strictly necessary as you can derive it from the index of the item in the list. It may be advantageous to use a simple List<int> that is sorted instead to prevent errors where you accidentally miss out a level, as in the solution you have already accepted.

If you want better performance you could use List.BinarySearch but I think the extra complexity is not worth it unless you have performance profiled and found that this is the bottleneck.

List<int> levels = new List<int> { 0, 100, 200, 400, 600 /* etc... */ };

int index = levels.BinarySearch(Experience);
int level;
if (index < 0)
{
    level = ~index;
}
else
{
    level = index + 1;
}
return level;