private Dictionary <Type, List <string> > GetSets()
{
DbContextTypesInitializersPair setsInfo;
if (!_objectSetInitializers.TryGetValue(_context.GetType(), out setsInfo))
{
var dbContextParam = Expression.Parameter(typeof(DbContext), "dbContext");
var initDelegates = new List <Action <DbContext> >();
var entityTypes = new Dictionary <Type, List <string> >();
foreach (var propertyInfo in _context.GetType().GetInstanceProperties().Where(p => p.GetIndexParameters().Length == 0 && p.DeclaringType != typeof(DbContext)))
{
var entityType = GetSetType(propertyInfo.PropertyType);
if (entityType != null)
{
if (!entityType.IsValidStructuralType())
{
throw new InvalidOperationException(entityType.Name);
}
List <string> properties;
if (!entityTypes.TryGetValue(entityType, out properties))
{
properties = new List <string>();
entityTypes[entityType] = properties;
}
properties.Add(propertyInfo.Name);
var setter = propertyInfo.Setter();
if (setter != null && setter.IsPublic)
{
var setMethod = SetMethod.MakeGenericMethod(entityType);
var newExpression = Expression.Call(dbContextParam, setMethod);
var setExpression = Expression.Call(Expression.Convert(dbContextParam, _context.GetType()), setter, newExpression);
initDelegates.Add(Expression.Lambda <Action <DbContext> >(setExpression, dbContextParam).Compile());
}
}
}
Action <DbContext> initializer = dbContext =>
{
foreach (var initer in initDelegates)
{
initer(dbContext);
}
};
setsInfo = new DbContextTypesInitializersPair(entityTypes, initializer);
_objectSetInitializers.TryAdd(_context.GetType(), setsInfo);
EntitySetCache.Initialize(entityTypes);
}
return(setsInfo.EntityTypeToPropertyNameMap);
}
// <summary>
// Processes the given context type to determine the DbSet or IDbSet
// properties and collect root entity types from those properties. Also, delegates are
// created to initialize any of these properties that have public setters.
// If the type has been processed previously in the app domain, then all this information
// is returned from a cache.
// </summary>
// <returns> A dictionary of potential entity type to the list of the names of the properties that used the type. </returns>
private Dictionary<Type, List<string>> GetSets()
{
DbContextTypesInitializersPair setsInfo;
if (!_objectSetInitializers.TryGetValue(_context.GetType(), out setsInfo))
{
// It is possible that multiple threads will enter this code and create the list
// and the delegates. However, the result will always be the same so we may, in
// the rare cases in which this happens, do some work twice, but functionally the
// outcome will be correct.
var dbContextParam = Expression.Parameter(typeof(DbContext), "dbContext");
var initDelegates = new List<Action<DbContext>>();
var entityTypes = new Dictionary<Type, List<string>>();
// Properties declared directly on DbContext such as Database are skipped
foreach (var propertyInfo in _context.GetType().GetInstanceProperties()
.Where(p => p.GetIndexParameters().Length == 0
&& p.DeclaringType != typeof(DbContext)))
{
var entityType = GetSetType(propertyInfo.PropertyType);
if (entityType != null)
{
// We validate immediately because a DbSet/IDbSet must be of
// a valid entity type since otherwise you could never use an instance.
if (!entityType.IsValidStructuralType())
{
throw Error.InvalidEntityType(entityType);
}
List<string> properties;
if (!entityTypes.TryGetValue(entityType, out properties))
{
properties = new List<string>();
entityTypes[entityType] = properties;
}
properties.Add(propertyInfo.Name);
if (DbSetPropertyShouldBeInitialized(propertyInfo))
{
var setter = propertyInfo.Setter();
if (setter != null && setter.IsPublic)
{
var setMethod = SetMethod.MakeGenericMethod(entityType);
var newExpression = Expression.Call(dbContextParam, setMethod);
var setExpression = Expression.Call(
Expression.Convert(dbContextParam, _context.GetType()), setter, newExpression);
initDelegates.Add(
Expression.Lambda<Action<DbContext>>(setExpression, dbContextParam).Compile());
}
}
}
}
Action<DbContext> initializer = dbContext =>
{
foreach (var initer in initDelegates)
{
initer(dbContext);
}
};
setsInfo = new DbContextTypesInitializersPair(entityTypes, initializer);
// If TryAdd fails it just means some other thread got here first, which is okay
// since the end result is the same info anyway.
_objectSetInitializers.TryAdd(_context.GetType(), setsInfo);
}
return setsInfo.EntityTypeToPropertyNameMap;
}
