Question

In an application I’m working on, I have what are essentially a bunch of lookup tables in a database which all contain two things: The ID (int) and a Value (string).

There’s only a handful of them, but I want to map all of them to a single Context which depends on the table name. Something like:

class LookupContext : DbContext
{
    public DbSet<Lookup> Lookups { get; set; }

    public LookupContext(String table)
    {
        // Pseudo code:
        // Bind Lookups based on what table is
        Lookups = MyDatabase.BindTo(table);
    }
}

So if I create a new LookupContext("foo"), it binds against the foo table. If I do new LookupContext("bar") it uses the bar table, and so forth.

Is there any way to do this? Or do I have to create a separate context + model for every table I have?

This is more or less my first time doing this, so I’m not really sure if what I’m doing is right.

Answer 1

The answer we should be able to give you is to use enums, but that’s not available quite yet – it’s in the next version of EF. See here for details: http://blogs.msdn.com/b/adonet/archive/2011/06/30/walkthrough-enums-june-ctp.aspx

With earlier versions of EF, you can simply create a class per lookup value (assuming state as an example) and have code that looks something like the following:

public class State
{
  public int StateId {get;set;}
  public string StateName {get;set;}
}

public class LookupContext : DbContext
{
  public DbSet<State> States {get;set;}
  // ... more lookups as DbSets
}

This will allow you to use one context but will still require one class per table. You can also use the fluent API if you want your table/column names to differ from your class/property names respectively. Hope that helps!