Question

For instance I have this bit of code

public class ProductService{
private IProductDataSource _dataSource = DependencyManager.Get<IProductDataSource>();
public Product Get(int id){
return _dataSource.Select(id);
}
}

I have 2 different data source:

• XML file which contains the informations only in 1 language,
• a SQL data base which contains the informations in many languages.

So I created 2 implementation for IProductDataSource, for for each kind of datasource.
But how do I send the required language to the SQL data source ?

• I add the parameter “language” to the method “IProductDataSource.Select” even if I won’t use it in the case of the XML implementation.
• Inside the SQL implementation I get the language from a global state ?
• I add the language to the constructor of my SQL implementation, but then I won’t use my DependencyManager and handle my self the dependency injection.

Maybe my first solution is not good.

Answer 1

The third option is the way to go. Inject the language configuration to your SQL implementation. Also get rid of your DependencyManager ServiceLocator and use constructor injection instead.