private static Type GetListItemType(Type type)
{
Type type1;
if (typeof (Array).IsAssignableFrom(type))
{
type1 = type.GetElementType();
}
else
{
PropertyInfo typedIndexer = DataRecordObjectView.GetTypedIndexer(type);
type1 = !(typedIndexer != (PropertyInfo) null) ? type : typedIndexer.PropertyType;
}
return type1;
}
/// <summary>
/// Return a list suitable for data binding using the supplied query results.
/// </summary>
/// <typeparam name="TElement"> CLR type of query result elements declared by the caller. </typeparam>
/// <param name="elementEdmTypeUsage"> The EDM type of the query results, used as the primary means of determining the CLR type of list returned by this method. </param>
/// <param name="queryResults"> IEnumerable used to enumerate query results used to populate binding list. Must not be null. </param>
/// <param name="objectContext">
/// <see cref="ObjectContext" /> associated with the query from which results were obtained. Must not be null.
/// </param>
/// <param name="forceReadOnly">
/// <b>True</b> to prevent modifications to the binding list built from the query result; otherwise <b>false</b> . Note that other conditions may prevent the binding list from being modified, so a value of <b>false</b> supplied for this parameter doesn't necessarily mean that the list will be writable.
/// </param>
/// <param name="singleEntitySet">
/// If the query results are composed of entities that only exist in a single
/// <see
/// cref="EntitySet" />
/// , the value of this parameter is the single EntitySet. Otherwise the value of this parameter should be null.
/// </param>
/// <returns>
/// <see cref="IBindingList" /> that is suitable for data binding.
/// </returns>
internal static IBindingList CreateViewForQuery <TElement>(
TypeUsage elementEdmTypeUsage, IEnumerable <TElement> queryResults, ObjectContext objectContext, bool forceReadOnly,
EntitySet singleEntitySet)
{
DebugCheck.NotNull(queryResults);
DebugCheck.NotNull(objectContext);
Type clrElementType = null;
var ospaceElementTypeUsage = GetOSpaceTypeUsage(elementEdmTypeUsage, objectContext);
// Map the O-Space EDM type to a CLR type.
// If the mapping is unsuccessful, fallback to TElement type.
if (ospaceElementTypeUsage == null)
{
clrElementType = typeof(TElement);
}
{
clrElementType = GetClrType <TElement>(ospaceElementTypeUsage.EdmType);
}
IBindingList objectView;
object eventDataSource = objectContext.ObjectStateManager;
// If the clrElementType matches the declared TElement type, optimize the construction of the ObjectView
// by avoiding a reflection-based instantiation.
if (clrElementType == typeof(TElement))
{
var viewData = new ObjectViewQueryResultData <TElement>(queryResults, objectContext, forceReadOnly, singleEntitySet);
objectView = new ObjectView <TElement>(viewData, eventDataSource);
}
else if (clrElementType == null)
{
var viewData = new ObjectViewQueryResultData <DbDataRecord>(queryResults, objectContext, true, null);
objectView = new DataRecordObjectView(viewData, eventDataSource, (RowType)ospaceElementTypeUsage.EdmType, typeof(TElement));
}
else
{
if (!typeof(TElement).IsAssignableFrom(clrElementType))
{
throw EntityUtil.ValueInvalidCast(clrElementType, typeof(TElement));
}
// Use reflection to create an instance of the generic ObjectView and ObjectViewQueryResultData classes,
// using clrElementType as the value of TElement generic type parameter for both classes.
var objectViewDataType = _genericObjectViewQueryResultDataType.MakeGenericType(clrElementType);
var viewDataConstructor = objectViewDataType.GetConstructor(
BindingFlags.Instance | BindingFlags.NonPublic,
null,
new[] { typeof(IEnumerable), typeof(ObjectContext), typeof(bool), typeof(EntitySet) },
null);
Debug.Assert(
viewDataConstructor != null,
"ObjectViewQueryResultData constructor not found. Please ensure constructor signature is correct.");
// Create ObjectViewQueryResultData instance
var viewData = viewDataConstructor.Invoke(new object[] { queryResults, objectContext, forceReadOnly, singleEntitySet });
// Create ObjectView instance
objectView = CreateObjectView(clrElementType, objectViewDataType, viewData, eventDataSource);
}
return(objectView);
}
PropertyDescriptorCollection ITypedList.GetItemProperties(
PropertyDescriptor[] listAccessors)
{
PropertyDescriptorCollection descriptorCollection;
if (listAccessors == null || listAccessors.Length == 0)
{
descriptorCollection = this._propertyDescriptorsCache;
}
else
{
PropertyDescriptor listAccessor = listAccessors[listAccessors.Length - 1];
FieldDescriptor fieldDescriptor = listAccessor as FieldDescriptor;
descriptorCollection = fieldDescriptor == null || fieldDescriptor.EdmProperty == null || fieldDescriptor.EdmProperty.TypeUsage.EdmType.BuiltInTypeKind != BuiltInTypeKind.RowType ? TypeDescriptor.GetProperties(DataRecordObjectView.GetListItemType(listAccessor.PropertyType)) : MaterializedDataRecord.CreatePropertyDescriptorCollection((StructuralType) fieldDescriptor.EdmProperty.TypeUsage.EdmType, typeof (IDataRecord), true);
}
return descriptorCollection;
}
