Can somebody clarify the C# is keyword please. In particular these 2 questions:

Q1) line 5; Why does this return true?

Q2) line 7; Why no cast exception?

public void Test()
{
    object intArray = new int[] { -100, -200 };            

    if (intArray is uint[]) //why does this return true?
    {
        uint[] uintArray = (uint[])intArray; //why no class cast exception?

        for (int x = 0; x < uintArray.Length; x++)
        {
            Console.Out.WriteLine(uintArray[x]);
        }
    }
}

MSDN's description does not clarify the situation. It states that is will return true if either of these conditions are met. (http://msdn.microsoft.com/en-us/library/scekt9xw(VS.71).aspx>MDSN Article)

expression is not null.
expression can be cast to type.

I don't believe that you can do a valid cast of int[] into uint[]. Because:

A) This code does not compile:

int[] signed = new int[] { -100 };
uint[] unsigned = (uint[])signed;

B) Doing the cast in the debugger gives an error:

(uint[])signed
"Cannot convert type 'int[]' to 'uint[]'"

Sure enough, if line 3 was int[] instead of object then it would never compile. Which brings me to a final question related to Q2.

Q3) Why does C# raise a cast/conversion error in the debugger and compiler but not at runtime?

c# arrays casting unsigned
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