/// <summary>
/// Wraps the collection in a DataReader, but also includes columns for the key attributes of related Entities.
/// </summary>
/// <typeparam name="T">The element type of the collection.</typeparam>
/// <param name="collection">A collection to wrap in a DataReader</param>
/// <param name="cx">The Entity Framework ObjectContext, used for metadata access</param>
/// <returns>A DbDataReader wrapping the collection.</returns>
public static IDataReader AsDataReader <T>(this IEnumerable <T> collection, ObjectContext context) where T : EntityObject
{
EntityDataReaderOptions options = EntityDataReaderOptions.Default;
options.RecreateForeignKeysForEntityFrameworkEntities = true;
return(new EntityDataReader <T>(collection, options, context));
}
/// <summary>
/// Wraps the collection in a DataReader, but also includes columns for the key attributes of related Entities.
/// </summary>
/// <typeparam name="T">The element type of the collectin.</typeparam>
/// <param name="collection">A collection to wrap in a DataReader</param>
/// <param name="detachObjects">Option to detach each object in the collection from the ObjectContext. This can reduce memory usage for queries returning large numbers of objects.</param>
/// <param name="prefixReladObjectColumns">If True, qualify the related object keys, if False don't</param>
/// <returns>A DbDataReader wrapping the collection.</returns>
/// <summary>
public static IDataReader AsDataReader <T>(this IEnumerable <T> collection, ObjectContext context, bool detachObjects, bool prefixRelatedObjectColumns) where T : EntityObject
{
EntityDataReaderOptions options = EntityDataReaderOptions.Default;
options.RecreateForeignKeysForEntityFrameworkEntities = true;
options.PrefixRelatedObjectColumns = prefixRelatedObjectColumns;
if (detachObjects)
{
return(new EntityDataReader <T>(collection.DetachAllFrom(context), options, context));
}
return(new EntityDataReader <T>(collection, options, context));
}
/// <summary>
/// Enumerates the collection and copies the data into a DataTable.
/// </summary>
/// <typeparam name="T">The element type of the collection.</typeparam>
/// <param name="collection">The collection to copy to a DataTable</param>
/// <returns>A DataTable containing the scalar projection of the collection.</returns>
public static DataTable ToDataTable <T>(this IEnumerable <T> collection)
{
DataTable t = new DataTable();
t.Locale = System.Globalization.CultureInfo.CurrentCulture;
t.TableName = typeof(T).Name;
EntityDataReaderOptions options = EntityDataReaderOptions.Default;
options.ExposeNullableTypes = false;
EntityDataReader <T> dr = new EntityDataReader <T>(collection, options);
t.Load(dr);
return(t);
}
/// <summary>
/// Enumerates the collection and copies the data into a DataTable, but also includes columns for the key attributes of related Entities.
/// </summary>
/// <typeparam name="T">The element type of the collection.</typeparam>
/// <param name="collection">The collection to copy to a DataTable</param>
/// <param name="cx">The Entity Framework ObjectContext, used for metadata access</param>
/// <returns>A DataTable containing the scalar projection of the collection.</returns>
public static DataTable ToDataTable <T>(this IEnumerable <T> collection, ObjectContext context) where T : EntityObject
{
DataTable t = new DataTable();
t.Locale = System.Globalization.CultureInfo.CurrentCulture;
t.TableName = typeof(T).Name;
EntityDataReaderOptions options = EntityDataReaderOptions.Default;
options.RecreateForeignKeysForEntityFrameworkEntities = true;
EntityDataReader <T> dr = new EntityDataReader <T>(collection, options, context);
t.Load(dr);
return(t);
}
public EntityDataReader(IEnumerable <T> col, EntityDataReaderOptions options, ObjectContext objectContext)
{
this.enumerator = col.GetEnumerator();
this.options = options;
if (options.RecreateForeignKeysForEntityFrameworkEntities && objectContext == null)
{
throw new ArgumentException("If RecreateForeignKeysForEntityFrameworkEntities=true then objectContext is required");
}
//done without a lock, so we risk running twice
if (scalarAttributes == null)
{
scalarAttributes = DiscoverScalarAttributes(typeof(T));
}
if (options.FlattenRelatedObjects && scalarAttributesPlusRelatedObjectScalarAttributes == null)
{
var atts = DiscoverRelatedObjectScalarAttributes(typeof(T));
scalarAttributesPlusRelatedObjectScalarAttributes = atts.Concat(scalarAttributes).ToList();
}
if (options.RecreateForeignKeysForEntityFrameworkEntities && scalarAttributesPlusRelatedObjectKeyAttributes == null)
{
var atts = DiscoverRelatedObjectKeyAttributes(typeof(T), objectContext);
scalarAttributesPlusRelatedObjectKeyAttributes = atts.Concat(scalarAttributes).ToList();
}
if (options.FlattenRelatedObjects)
{
this.attributes = scalarAttributesPlusRelatedObjectScalarAttributes;
}
else if (objectContext != null)
{
this.attributes = scalarAttributesPlusRelatedObjectKeyAttributes;
}
else
{
this.attributes = scalarAttributes;
}
}
/// <summary>
/// Wraps the IEnumerable in a DbDataReader, having one column for each "scalar" property of the type T.
/// The collection will be enumerated as the client calls IDataReader.Read().
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="collection"></param>
/// <returns></returns>
public static IDataReader AsDataReader <T>(this IEnumerable <T> collection, bool exposeNullableColumns, bool flattenRelatedObjects)
{
EntityDataReaderOptions options = new EntityDataReaderOptions(exposeNullableColumns, flattenRelatedObjects, true, false);
return(new EntityDataReader <T>(collection, options, null));
}
public EntityDataReader(IEnumerable <T> col, EntityDataReaderOptions options)
: this(col, options, null)
{
}
