static void Main(string[] args)
{
// Run a query for each Account using the default/global filters.
var context1 = new ExampleContext();
// Test for multiple navigation properties - issue #17
var list = context1.EntityASet.Include(a => a.Nav1).Include(a => a.Nav2).Include(a => a.Nav3).ToList();
System.Diagnostics.Debug.Assert((list.Count == 2) && (list[0].Nav1 != null) && (list[0].Nav2 == null) && (list[1].Nav1 != null) && (list[1].Nav2 == null));
//var secondContext = new SecondContext();
//var list = context1.BlogEntries.ToList();
//Console.WriteLine("Got {0} items", list.Count());
//context1.DisableFilter("BlogContainsTest");
//list = context1.BlogEntries.ToList();
//Console.WriteLine("Got {0} items", list.Count());
//list = secondContext.BlogEntries.ToList();
//System.Diagnostics.Debug.Print("Got {0} items", list.Count());
Console.WriteLine("");
Console.WriteLine("Querying with IsDeleted filter enabled");
Query(context1, "homer", 2, true);
Query(context1, "bart", 3, true);
{
// Query each account with the IsDeleted filter disabled. The filter is disabled
// by setting the value to null using SetFilterScopedParameterValue() so that it applies
// ONLY to this context and will not affect any other active or future contexts.
var context2 = new ExampleContext();
context2.DisableFilter("BlogEntryFilter");
Console.WriteLine("");
Console.WriteLine("Querying with BlogEntryFilter filter disabled");
Query(context2, "homer", 9, false);
Query(context2, "bart", 9, false);
// Re-enable the filter and query for deleted records
context2.EnableFilter("BlogEntryFilter");
context2.SetFilterScopedParameterValue("BlogEntryFilter", "isDeleted", true);
Console.WriteLine("");
Console.WriteLine("Querying for deleted records only");
Query(context2, "homer", 2, true, true);
Query(context2, "bart", 2, true, true);
}
// Re-query using the original context1 object to demonstrate that the changes
// made to context2 have no effect on it and were properly scoped.
Console.WriteLine("");
Console.WriteLine("Re-Querying with original context");
Query(context1, "homer", 2, true);
Query(context1, "bart", 3, true);
Console.WriteLine("");
Console.WriteLine("");
Console.WriteLine("Press enter to close...");
Console.ReadLine();
}
private static void Query(ExampleContext context, string userName, int expected, bool blogFilterIsEnabled, bool reusedContext = false)
{
var account = context.Accounts
.Include(a => a.BlogEntries)
.Where(a => a.UserName == userName).FirstOrDefault();
// Set the CurrentAccountID in the static/global property used in the filter definition (see ExampleContext.OnModelCreating)
// For creating a filter on the current user, this could come from the Thread.CurrentPrincipal...
ExampleContext.CurrentAccountID = account.ID;
if (blogFilterIsEnabled)
{
// Don't do this check if the blog filter is disabled. Otherwise, the blog records in account.BlogEntries
// will be filtered by the Account.ID while allBlogEntries will not (since the AccountID filter is now
// part of the "BlogEntryFilter" filter).
// Test to make sure that Include()'d collections are also filtered
var allBlogEntries = context.BlogEntries.ToList();
if (account.BlogEntries.Count != allBlogEntries.Count)
{
// This will happen if the context is being reused and EF already has other blog entries cached. Those
// cached objects will be automatically attached to the account object even if they do not match the
// current sql query filter. There is nothing that can be done about this. Care should be taken to
// not re-use the same DbContext when filter values are changed.
// See https://github.com/jcachat/EntityFramework.DynamicFilters/issues/5
System.Diagnostics.Debug.Print("account.BlogEntries={0}, allBlogEntries={1}, reusedContext={2}", account.BlogEntries.Count, allBlogEntries.Count, reusedContext);
System.Diagnostics.Debug.Assert(reusedContext);
}
}
// Query blog entries. This will use the global filter created in ExampleContext.OnModelCreating.
// Filter on IsActive is to reproduce a situation seen with MySQL that was adding those filters and not enclosing them in ()'s so the
// 'or' condition here was not properly enclosed - caused our dynamic filters to not be used correctly.
bool?active = true;
var blogEntries = context.BlogEntries.Where(b => (!active.HasValue || (b.IsActive == active.Value))).ToList();
System.Diagnostics.Debug.Assert(blogEntries.Count == expected);
Console.WriteLine(string.Format("Current User = {0}: Selected {1} blog entries", userName, blogEntries.Count));
if (blogEntries.Count != expected)
{
Console.WriteLine(string.Format(" *** Expected {0} blog entries!", expected));
}
}
