It seems like the most simplistic things are hard to figure out sometimes... Many code references have the type TEntity used for generic handling of entities in an entity data model. I tried to use it in my code and get: "Unknown type 'TEntity'" what gives??? Why do I get "Unknown type"? Is this only available in .net 4.0?
BTW: Using .net 3.5.
I'm trying to use code from this book:
public TEntity ExecuteFirstorDefault<TEntity>(ObjectQuery<TEntity> objectQuery)
{
try
{
return objectQuery.FirstOrDefault();
}
catch (EntitySqlException ex)
{
throw ex; //TODO: Replace with handling code
//additional exceptions as described in Chapter 18
}
}
1 Answer
TEntity is a generic type parameter, not a concrete type.
I guess my question is why I can't use it, why do I get Unknown type.
Because it's not a concrete type.
Say you have a generic list implementation, declared as List<T>. T is a type parameter, which means that it does not represent a specific type. As the programmer, you have to instruct the compiler to use a specific type to use, rather than the generic type T, by providing a type argument. You could create a list of integers like so:
List<int> myInts = new List<int>();
In this example, the type argument is int. All the generic methods (or properties) of List that accept or return a T will instead use int.
