/// <summary>
/// This is an internal API that supports the Entity Framework Core infrastructure and not subject to
/// the same compatibility standards as public APIs. It may be changed or removed without notice in
/// any release. You should only use it directly in your code with extreme caution and knowing that
/// doing so can result in application failures when updating to a new Entity Framework Core release.
/// </summary>
public override IRelationalValueBufferFactory CreateValueBufferFactory(
IRelationalValueBufferFactoryFactory relationalValueBufferFactoryFactory, DbDataReader dataReader)
{
Check.NotNull(relationalValueBufferFactoryFactory, nameof(relationalValueBufferFactoryFactory));
Check.NotNull(dataReader, nameof(dataReader));
var readerColumns
= Enumerable
.Range(0, dataReader.FieldCount)
.Select(
i => new
{
Name = dataReader.GetName(i),
Ordinal = i
})
.ToList();
var types = new TypeMaterializationInfo[SelectExpression.Projection.Count];
for (var i = 0; i < SelectExpression.Projection.Count; i++)
{
if (SelectExpression.Projection[i] is ColumnExpression columnExpression)
{
var columnName = columnExpression.Name;
if (columnName != null)
{
var readerColumn
= readerColumns.SingleOrDefault(
c =>
string.Equals(columnName, c.Name, StringComparison.OrdinalIgnoreCase));
if (readerColumn == null)
{
throw new InvalidOperationException(RelationalStrings.FromSqlMissingColumn(columnName));
}
types[i] = new TypeMaterializationInfo(
columnExpression.Type,
columnExpression.Property,
Dependencies.TypeMappingSource,
fromLeftOuterJoin: false,
readerColumn.Ordinal);
}
}
}
return(relationalValueBufferFactoryFactory.Create(types));
}
private static Expression CreateGetValueExpression(
Expression dataReaderExpression,
int index,
TypeMaterializationInfo materializationInfo,
bool detailedErrorsEnabled,
bool box = true)
{
var getMethod = materializationInfo.Mapping.GetDataReaderMethod();
index = materializationInfo.Index == -1 ? index : materializationInfo.Index;
var indexExpression = Expression.Constant(index);
Expression valueExpression
= Expression.Call(
getMethod.DeclaringType != typeof(DbDataReader)
? Expression.Convert(dataReaderExpression, getMethod.DeclaringType)
: dataReaderExpression,
getMethod,
indexExpression);
valueExpression = materializationInfo.Mapping.CustomizeDataReaderExpression(valueExpression);
var converter = materializationInfo.Mapping.Converter;
if (converter != null)
{
if (valueExpression.Type != converter.ProviderClrType)
{
valueExpression = Expression.Convert(valueExpression, converter.ProviderClrType);
}
valueExpression = ReplacingExpressionVisitor.Replace(
converter.ConvertFromProviderExpression.Parameters.Single(),
valueExpression,
converter.ConvertFromProviderExpression.Body);
}
if (valueExpression.Type != materializationInfo.ModelClrType)
{
valueExpression = Expression.Convert(valueExpression, materializationInfo.ModelClrType);
}
var exceptionParameter
= Expression.Parameter(typeof(Exception), name: "e");
var property = materializationInfo.Property;
if (detailedErrorsEnabled)
{
var catchBlock
= Expression
.Catch(
exceptionParameter,
Expression.Call(
_throwReadValueExceptionMethod
.MakeGenericMethod(valueExpression.Type),
exceptionParameter,
Expression.Call(
dataReaderExpression,
_getFieldValueMethod.MakeGenericMethod(typeof(object)),
indexExpression),
Expression.Constant(property, typeof(IPropertyBase))));
valueExpression = Expression.TryCatch(valueExpression, catchBlock);
}
if (box && valueExpression.Type.GetTypeInfo().IsValueType)
{
valueExpression = Expression.Convert(valueExpression, typeof(object));
}
if (property?.IsNullable != false ||
property.DeclaringEntityType.BaseType != null ||
materializationInfo.IsFromLeftOuterJoin != false)
{
valueExpression
= Expression.Condition(
Expression.Call(dataReaderExpression, _isDbNullMethod, indexExpression),
Expression.Default(valueExpression.Type),
valueExpression);
}
return(valueExpression);
}
/// <summary> /// Determines whether the specified object is equal to the current object. /// </summary> /// <param name="other">The object to compare with the current object.</param> /// <returns><see langword="true" /> if the specified object is equal to the current object; otherwise, <see langword="false" />.</returns> protected virtual bool Equals(TypeMaterializationInfo other) => ProviderClrType == other.ProviderClrType && ModelClrType == other.ModelClrType && Equals(Mapping, other.Mapping) && Equals(Property, other.Property) && IsNullable == other.IsNullable;
