Unboxing to unknown type
- by Robert
I'm trying to figure out syntax that supports unboxing an integral type (short/int/long) to its intrinsic type, when the type itself is unknown.
Here is a completely contrived example that demonstrates the concept:
// Just a simple container that returns values as objects
struct DataStruct
{
public short ShortVale;
public int IntValue;
public long LongValue;
public object GetBoxedShortValue() { return LongValue; }
public object GetBoxedIntValue() { return LongValue; }
public object GetBoxedLongValue() { return LongValue; }
}
static void Main( string[] args )
{
DataStruct data;
// Initialize data - any value will do
data.LongValue = data.IntValue = data.ShortVale = 42;
DataStruct newData;
// This works if you know the type you are expecting!
newData.ShortVale = (short)data.GetBoxedShortValue();
newData.IntValue = (int)data.GetBoxedIntValue();
newData.LongValue = (long)data.GetBoxedLongValue();
// But what about when you don't know?
newData.ShortVale = data.GetBoxedShortValue(); // error
newData.IntValue = data.GetBoxedIntValue(); // error
newData.LongValue = data.GetBoxedLongValue(); // error
}
In each case, the integral types are consistent, so there should be some form of syntax that says "the object contains a simple type of X, return that as X (even though I don't know what X is)". Because the objects ultimately come from the same source, there really can't be a mismatch (short != long).
I apologize for the contrived example, it seemed like the best way to demonstrate the syntax.
Thanks.
