C#: Getting size of a value-type variable at runtime?

Question

I know languages such as C and C++ allow determining the size of data (structs, arrays, variables...) at runtime using sizeof() function. I tried that in C# and apparently i

Answer 1

public static class TypeSize
{
    public static int GetSize(this T value)
    {
        if (typeof(T).IsArray)
        {
            var elementSize = GetTypeSize(typeof(T).GetElementType());
            var length = (value as Array)?.GetLength(0);
            return length.GetValueOrDefault(0) * elementSize;
        }
        return GetTypeSize(typeof(T));
    }

    static ConcurrentDictionary _cache = new ConcurrentDictionary();

    static int GetTypeSize(Type type)
    {
        return _cache.GetOrAdd(type, _ =>
        {
            var dm = new DynamicMethod("SizeOfType", typeof(int), new Type[0]);
            ILGenerator il = dm.GetILGenerator();
            il.Emit(OpCodes.Sizeof, type);
            il.Emit(OpCodes.Ret);
            return (int)dm.Invoke(null, null);
        });
    }
}