We were playing with Nullable types this week - came across some interesting methods that are available to interrogate Nullable types.

To get at the underlying data type in the Nullable type:
System.Nullable.GetUnderlyingType(type)

And to find out more about a Type, whether it's a generic, whether it's a Nullable type, and what are the generic template arguments...

string s = "23";
object o = Convert.ChangeType( s, typeof( int ) );

Nullable ni = 3;
Type t = ni.GetType();

Type t2 = typeof( Nullable );

if ( t2.IsGenericType && t2.GetGenericTypeDefinition() == typeof(Nullable<>))
{
 Type baseType = t2.GetGenericArguments()[0];
 object o2 = Convert.ChangeType( s, baseType );
 //return Activator.CreateInstance(ft, val);
}

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