/// <summary>
/// ScalarColumnMap
/// </summary>
/// <param name="columnMap"></param>
/// <param name="replacementVarMap"></param>
/// <returns></returns>
internal override ColumnMap Visit(ScalarColumnMap columnMap, VarMap replacementVarMap)
{
return(new ScalarColumnMap(columnMap.Type, columnMap.Name, columnMap.CommandId, columnMap.ColumnPos));
}
internal abstract TResultType Visit(ScalarColumnMap columnMap, TArgType arg);
/// <summary>
/// Requires: a public type with a public, default constructor. Returns a column map initializing the type
/// and all properties of the type with a public setter taking a primitive type and having a corresponding
/// column in the reader.
/// </summary>
internal static CollectionColumnMap CreateColumnMapFromReaderAndClrType(DbDataReader reader, Type type, MetadataWorkspace workspace)
{
Debug.Assert(null != reader);
Debug.Assert(null != type);
Debug.Assert(null != workspace);
// we require a default constructor
ConstructorInfo constructor = type.GetConstructor(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance,
null, Type.EmptyTypes, null);
if (type.IsAbstract || (null == constructor && !type.IsValueType))
{
throw EntityUtil.InvalidOperation(
Strings.ObjectContext_InvalidTypeForStoreQuery(type));
}
// build a LINQ expression used by result assembly to create results
var memberInfo = new List <Tuple <MemberAssignment, int, EdmProperty> >();
foreach (PropertyInfo prop in type.GetProperties(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance))
{
// for enums unwrap the type if nullable
var propertyUnderlyingType = Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType;
Type propType = propertyUnderlyingType.IsEnum ? propertyUnderlyingType.GetEnumUnderlyingType() : prop.PropertyType;
EdmType modelType;
int ordinal;
if (TryGetColumnOrdinalFromReader(reader, prop.Name, out ordinal) &&
MetadataHelper.TryDetermineCSpaceModelType(propType, workspace, out modelType) &&
(Helper.IsScalarType(modelType)) &&
prop.CanWrite && prop.GetIndexParameters().Length == 0 && null != prop.GetSetMethod(/* nonPublic */ true))
{
memberInfo.Add(Tuple.Create(
Expression.Bind(prop, Expression.Parameter(prop.PropertyType, "placeholder")),
ordinal,
new EdmProperty(prop.Name, TypeUsage.Create(modelType))));
}
}
// initialize members in the order in which they appear in the reader
MemberInfo[] members = new MemberInfo[memberInfo.Count];
MemberBinding[] memberBindings = new MemberBinding[memberInfo.Count];
ColumnMap[] propertyMaps = new ColumnMap[memberInfo.Count];
EdmProperty[] modelProperties = new EdmProperty[memberInfo.Count];
int i = 0;
foreach (var memberGroup in memberInfo.GroupBy(tuple => tuple.Item2).OrderBy(tuple => tuple.Key))
{
// make sure that a single column isn't contributing to multiple properties
if (memberGroup.Count() != 1)
{
throw EntityUtil.InvalidOperation(Strings.ObjectContext_TwoPropertiesMappedToSameColumn(
reader.GetName(memberGroup.Key),
String.Join(", ", memberGroup.Select(tuple => tuple.Item3.Name).ToArray())));
}
var member = memberGroup.Single();
MemberAssignment assignment = member.Item1;
int ordinal = member.Item2;
EdmProperty modelProp = member.Item3;
members[i] = assignment.Member;
memberBindings[i] = assignment;
propertyMaps[i] = new ScalarColumnMap(modelProp.TypeUsage, modelProp.Name, 0, ordinal);
modelProperties[i] = modelProp;
i++;
}
NewExpression newExpr = null == constructor?Expression.New(type) : Expression.New(constructor);
MemberInitExpression init = Expression.MemberInit(newExpr, memberBindings);
InitializerMetadata initMetadata = InitializerMetadata.CreateProjectionInitializer(
(EdmItemCollection)workspace.GetItemCollection(DataSpace.CSpace), init, members);
// column map (a collection of rows with InitializerMetadata markup)
RowType rowType = new RowType(modelProperties, initMetadata);
RecordColumnMap rowMap = new RecordColumnMap(TypeUsage.Create(rowType),
"DefaultTypeProjection", propertyMaps, null);
CollectionColumnMap collectionMap = new SimpleCollectionColumnMap(rowType.GetCollectionType().TypeUsage,
rowType.Name, rowMap, null, null);
return(collectionMap);
}
internal virtual void Visit(ScalarColumnMap columnMap, TArgType arg)
{
}