C#/.NET: Why can't I cast this decimal to an int? [duplicate]

This question already has answers here: Closed 11 years ago.

Possible Duplicate:

Why can't I unbox an int as a decimal?

Okay, C#/.NET gurus, can someone tell me why this cast works:

static void Main(string[] args)
{
    int _int = 0;
    decimal _decimal = 1;

    _int = (int)_decimal;

    Console.ReadLine();
}

...but nei开发者_StackOverflow社区ther of these do?

static void Main(string[] args)
{
    int _int = 0;
    decimal d = 1;
    object _decimal = d;

    _int = (int)_decimal;

    Console.ReadLine();
}

static void Main(string[] args)
{
    int _int = 0;
    object _decimal = 1M;

    _int = (int)_decimal;

    Console.ReadLine();
}

I can cast a decimal to an int so long as what I am casting from is an explicitly-declared decimal type, but I can't cast a decimal to an int when the decimal is stored in an object type? What's up with that?

NOTE: I know I can probably use Convert.ToInt32(), but I am trying to figure out this this here is not working.

---

Because there is an explicit conversion defined in the framework from decimal to int. Read this MSDN documentation.