Compile-time type checking

Question

Hi! I have this (for me it's a big problem)problem, the first one is how can you pass a DBNull & a null value in an integer type varible/property? I have come up with the solution to this problem by making the variable/property to an object type. But in an object type variable/property you can pass any data type value and I only want to pass an int type, DBnull & null value to this variable/property. I know you can do this by the GetType method but i want to filter it during compile time. I don't know if it's possible but any suggesstions will be welcome. Thank you very much!

ssswamii · Answer

That's a good question one Microsoft will be addressing in the Whidbey release of the CLR in 2004 via a new feature called generics. Generics will allow reusable types by doing compile time checks rather than runtime casts allowing for better performance and more code reusability. For now I see 2 options: you could write a property that would get/set object types but would do a check first to see if it's an int DBnull or null. object myVar = null; public object MyProperty { get { return myVar; } set { if(value.GetType() != typeof(int) && value.GetType() != typeof(DBNull) && value != null) throw new Exception(You're only allowed to store ints DBNull and null types); myVar = value; } } The other way would be to create a class that stores an int or a DBNull then use a property to get/set an instance of that class then in the set property set only the int or DBNull value.