In csharp, how to convert intArray to chararray, and the difference of csharp 2 and 3.

ConvertIntarrayToChararray.cs

public class ConvertIntarrayToChararray
{
    public int FindMaxConsecutiveOnes(int[] nums) {
        char[] numsToChars = new char[nums.Length];
        numsToChars = nums.ConvertAll<int, char>(nums, c => char.Parse(c));  // C# 3.0 
        // In C# 2.0, replaced the above code to :
        // numsToChars.ConvertAll<int, char>(nums, delegate(int c) { return char.Parse(c)});
    }
}

Maybe it's wrong, because I don't think about covariance and contravariance in generics. 😳