Querying an Entity Data Model - Entity Framework 6 Recipes - page 101

static void RunExample()
{
using (var context = new EFRecipesEntities())
{
// delete previous test data
context.Database.ExecuteSqlCommand("delete from chapter3.patron");
// add new test data
context.Patrons.Add(new Patron { Name = "Jill Roberts",
SponsorType = (int)SponsorTypes.ContributesMoney });
context.Patrons.Add(new Patron { Name = "Ryan Keyes",
// note the useage of the bitwise OR operator: '|'
SponsorType = (int)(SponsorTypes.ContributesMoney |
SponsorTypes.IsABoardMember)});
context.Patrons.Add(new Patron {Name = "Karen Rosen",
SponsorType = (int)SponsorTypes.Volunteers});
context.Patrons.Add(new Patron {Name = "Steven King",
SponsorType = (int)(SponsorTypes.ContributesMoney |
SponsorTypes.Volunteers)});
context.SaveChanges();
}
using (var context = new EFRecipesEntities())
{
Console.WriteLine("Using LINQ...");
var sponsors = from p in context.Patrons
// note the useage of the bitwise AND operator: '&'
where (p.SponsorType &
(int)SponsorTypes.ContributesMoney) != 0
select p;
Console.WriteLine("Patrons who contribute money");
foreach (var sponsor in sponsors)
{
Console.WriteLine("\t{0}", sponsor.Name);
}
}
using (var context = new EFRecipesEntities())
{
Console.WriteLine("\nUsing Entity SQL...");
var esql = @"select value p from Patrons as p
where BitWiseAnd(p.SponsorType, @type) <> 0";
var sponsors = ((IObjectContextAdapter)context).ObjectContext.CreateQuery<Patron>(esql,
new ObjectParameter("type", (int)SponsorTypes.ContributesMoney));
Console.WriteLine("Patrons who contribute money");
foreach (var sponsor in sponsors)
{
Console.WriteLine("\t{0}", sponsor.Name);
}
}
}