internal static bool TryGetIsUnicode(TypeUsage type, out bool isUnicode)
{
if (!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.String))
{
isUnicode = false;
return(false);
}
return(TypeHelpers.TryGetBooleanFacetValue(type, DbProviderManifest.UnicodeFacetName, out isUnicode));
}
internal DbFilterExpression(TypeUsage resultType, DbExpressionBinding input, DbExpression predicate)
: base(DbExpressionKind.Filter, resultType)
{
Debug.Assert(input != null, "DbFilterExpression input cannot be null");
Debug.Assert(predicate != null, "DbBFilterExpression predicate cannot be null");
Debug.Assert(TypeSemantics.IsPrimitiveType(predicate.ResultType, PrimitiveTypeKind.Boolean), "DbFilterExpression predicate must have a Boolean result type");
_input = input;
_predicate = predicate;
}
internal static bool SupportsCastToString(TypeUsage typeUsage)
{
return(TypeSemantics.IsPrimitiveType(typeUsage, PrimitiveTypeKind.String) ||
TypeSemantics.IsNumericType(typeUsage) ||
TypeSemantics.IsBooleanType(typeUsage) ||
TypeSemantics.IsPrimitiveType(typeUsage, PrimitiveTypeKind.DateTime) ||
TypeSemantics.IsPrimitiveType(typeUsage, PrimitiveTypeKind.DateTimeOffset) ||
TypeSemantics.IsPrimitiveType(typeUsage, PrimitiveTypeKind.Time) ||
TypeSemantics.IsPrimitiveType(typeUsage, PrimitiveTypeKind.Guid));
}
internal static bool TryGetScale(TypeUsage type, out byte scale)
{
if (!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.Decimal))
{
scale = 0;
return(false);
}
return(TryGetByteFacetValue(type, DbProviderManifest.ScaleFacetName, out scale));
}
internal static bool TryGetPrecision(TypeUsage type, out byte precision)
{
if (!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.Decimal))
{
precision = 0;
return(false);
}
return(TypeHelpers.TryGetByteFacetValue(type, DbProviderManifest.PrecisionFacetName, out precision));
}
internal DbQuantifierExpression(DbExpressionKind kind, TypeUsage booleanResultType, DbExpressionBinding input, DbExpression predicate)
: base(kind, booleanResultType)
{
Debug.Assert(input != null, "DbQuantifierExpression input cannot be null");
Debug.Assert(predicate != null, "DbQuantifierExpression predicate cannot be null");
Debug.Assert(TypeSemantics.IsPrimitiveType(booleanResultType, PrimitiveTypeKind.Boolean), "DbQuantifierExpression must have a Boolean result type");
Debug.Assert(TypeSemantics.IsPrimitiveType(predicate.ResultType, PrimitiveTypeKind.Boolean), "DbQuantifierExpression predicate must have a Boolean result type");
this._input = input;
this._predicate = predicate;
}
internal DbFilterExpression(TypeUsage resultType, DbExpressionBinding input, DbExpression predicate)
: base(DbExpressionKind.Filter, resultType)
{
DebugCheck.NotNull(input);
DebugCheck.NotNull(predicate);
Debug.Assert(
TypeSemantics.IsPrimitiveType(predicate.ResultType, PrimitiveTypeKind.Boolean),
"DbFilterExpression predicate must have a Boolean result type");
_input = input;
_predicate = predicate;
}
internal static bool TryGetMaxLength(TypeUsage type, out int maxLength)
{
if (!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.String) &&
!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.Binary))
{
maxLength = 0;
return(false);
}
// Binary and String FixedLength facets share the same name
return(TypeHelpers.TryGetIntFacetValue(type, DbProviderManifest.MaxLengthFacetName, out maxLength));
}
private static void BuildTypeName(StringBuilder text, TypeUsage type)
{
var rowType = type.EdmType as RowType;
var collType = type.EdmType as CollectionType;
var refType = type.EdmType as RefType;
if (TypeSemantics.IsPrimitiveType(type))
{
text.Append(type);
}
else if (collType != null)
{
text.Append("Collection{");
BuildTypeName(text, collType.TypeUsage);
text.Append("}");
}
else if (refType != null)
{
text.Append("Ref<");
AppendFullName(text, refType.ElementType);
text.Append(">");
}
else if (rowType != null)
{
text.Append("Record[");
var idx = 0;
foreach (var recColumn in rowType.Properties)
{
text.Append("'");
text.Append(recColumn.Name);
text.Append("'");
text.Append("=");
BuildTypeName(text, recColumn.TypeUsage);
idx++;
if (idx < rowType.Properties.Count)
{
text.Append(", ");
}
}
text.Append("]");
}
else
{
// Entity, Relationship, Complex
if (!string.IsNullOrEmpty(type.EdmType.NamespaceName))
{
text.Append(type.EdmType.NamespaceName);
text.Append(".");
}
text.Append(type.EdmType.Name);
}
}
internal static bool TryGetIsFixedLength(TypeUsage type, out bool isFixedLength)
{
if (!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.String)
&&
!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.Binary))
{
isFixedLength = false;
return(false);
}
// Binary and String MaxLength facets share the same name
return(TryGetBooleanFacetValue(type, DbProviderManifest.FixedLengthFacetName, out isFixedLength));
}
private static void BuildTypeName(StringBuilder text, TypeUsage type)
{
RowType edmType1 = type.EdmType as RowType;
CollectionType edmType2 = type.EdmType as CollectionType;
RefType edmType3 = type.EdmType as RefType;
if (TypeSemantics.IsPrimitiveType(type))
{
text.Append((object)type);
}
else if (edmType2 != null)
{
text.Append("Collection{");
ExpressionPrinter.PrinterVisitor.BuildTypeName(text, edmType2.TypeUsage);
text.Append("}");
}
else if (edmType3 != null)
{
text.Append("Ref<");
ExpressionPrinter.PrinterVisitor.AppendFullName(text, (EdmType)edmType3.ElementType);
text.Append(">");
}
else if (edmType1 != null)
{
text.Append("Record[");
int num = 0;
foreach (EdmProperty property in edmType1.Properties)
{
text.Append("'");
text.Append(property.Name);
text.Append("'");
text.Append("=");
ExpressionPrinter.PrinterVisitor.BuildTypeName(text, property.TypeUsage);
++num;
if (num < edmType1.Properties.Count)
{
text.Append(", ");
}
}
text.Append("]");
}
else
{
if (!string.IsNullOrEmpty(type.EdmType.NamespaceName))
{
text.Append(type.EdmType.NamespaceName);
text.Append(".");
}
text.Append(type.EdmType.Name);
}
}
private static string GetTypeUsageToken(TypeUsage type)
{
string result = null;
// Dev10#537010: EntityCommand false positive cache hits caused by insufficient parameter type information in cache key
// Ensure String types are correctly differentiated.
if (ReferenceEquals(type, DbTypeMap.AnsiString))
{
result = "AnsiString";
}
else if (ReferenceEquals(type, DbTypeMap.AnsiStringFixedLength))
{
result = "AnsiStringFixedLength";
}
else if (ReferenceEquals(type, DbTypeMap.String))
{
result = "String";
}
else if (ReferenceEquals(type, DbTypeMap.StringFixedLength))
{
result = "StringFixedLength";
}
else if (ReferenceEquals(type, DbTypeMap.Xml))
{
// Xml is currently mapped to (unicode, variable-length) string, so the TypeUsage
// given to the provider is actually a String TypeUsage.
Debug.Assert(
TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.String),
"Update GetTypeUsageToken to return 'Xml' for Xml parameters");
result = "String";
}
else if (TypeSemantics.IsEnumerationType(type))
{
result = type.EdmType.FullName;
}
else
{
// String/Xml TypeUsages are the only DbType-derived TypeUsages that carry meaningful facets.
// Otherwise, the primitive type name is a sufficient token (note that full name is not required
// since model types always have the 'Edm' namespace).
Debug.Assert(TypeSemantics.IsPrimitiveType(type), "EntityParameter TypeUsage not a primitive type?");
Debug.Assert(
!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.String),
"String TypeUsage not derived from DbType.AnsiString, AnsiString, String, StringFixedLength or Xml?");
result = type.EdmType.Name;
}
return(result);
}
internal DbLikeExpression(TypeUsage booleanResultType, DbExpression input, DbExpression pattern, DbExpression escape)
: base(DbExpressionKind.Like, booleanResultType)
{
Debug.Assert(input != null, "DbLikeExpression argument cannot be null");
Debug.Assert(pattern != null, "DbLikeExpression pattern cannot be null");
Debug.Assert(escape != null, "DbLikeExpression escape cannot be null");
Debug.Assert(TypeSemantics.IsPrimitiveType(input.ResultType, PrimitiveTypeKind.String), "DbLikeExpression argument must have a string result type");
Debug.Assert(TypeSemantics.IsPrimitiveType(pattern.ResultType, PrimitiveTypeKind.String), "DbLikeExpression pattern must have a string result type");
Debug.Assert(TypeSemantics.IsPrimitiveType(escape.ResultType, PrimitiveTypeKind.String), "DbLikeExpression escape must have a string result type");
Debug.Assert(TypeSemantics.IsBooleanType(booleanResultType), "DbLikeExpression must have a Boolean result type");
this._argument = input;
this._pattern = pattern;
this._escape = escape;
}
internal DbLikeExpression(TypeUsage booleanResultType, DbExpression input, DbExpression pattern, DbExpression escape)
: base(DbExpressionKind.Like, booleanResultType)
{
DebugCheck.NotNull(input);
DebugCheck.NotNull(pattern);
DebugCheck.NotNull(escape);
Debug.Assert(
TypeSemantics.IsPrimitiveType(input.ResultType, PrimitiveTypeKind.String),
"DbLikeExpression argument must have a string result type");
Debug.Assert(
TypeSemantics.IsPrimitiveType(pattern.ResultType, PrimitiveTypeKind.String),
"DbLikeExpression pattern must have a string result type");
Debug.Assert(
TypeSemantics.IsPrimitiveType(escape.ResultType, PrimitiveTypeKind.String),
"DbLikeExpression escape must have a string result type");
Debug.Assert(TypeSemantics.IsBooleanType(booleanResultType), "DbLikeExpression must have a Boolean result type");
_argument = input;
_pattern = pattern;
_escape = escape;
}
/// <summary>
/// Adds the flattened properties on the input to the flattenedProperties list.
/// </summary>
/// <param name="input"></param>
/// <param name="flattenedProperties"></param>
private void FlattenProperties(DbExpression input, IList <DbPropertyExpression> flattenedProperties)
{
IList <EdmProperty> properties = TypeHelpers.GetProperties(input.ResultType);
Debug.Assert(properties.Count != 0, "No nested properties when FlattenProperties called?");
for (int i = 0; i < properties.Count; i++)
{
DbExpression propertyInput = input;
DbPropertyExpression propertyExpression = propertyInput.Property(properties[i]);
if (TypeSemantics.IsPrimitiveType(properties[i].TypeUsage))
{
flattenedProperties.Add(propertyExpression);
}
else
{
Debug.Assert(TypeSemantics.IsEntityType(properties[i].TypeUsage) || TypeSemantics.IsRowType(properties[i].TypeUsage),
"The input to FlattenProperties is not of EntityType or RowType?");
FlattenProperties(propertyExpression, flattenedProperties);
}
}
}
internal DbNotExpression(TypeUsage booleanResultType, DbExpression argument)
: base(DbExpressionKind.Not, booleanResultType, argument)
{
Debug.Assert(TypeSemantics.IsPrimitiveType(booleanResultType, PrimitiveTypeKind.Boolean), "DbNotExpression requires a Boolean result type");
}
protected override void SetDbParameterValue(DbParameter parameter, TypeUsage parameterType, object value)
{
// Ensure a value that can be used with SqlParameter
value = EnsureSqlParameterValue(value);
if (TypeSemantics.IsPrimitiveType(parameterType, PrimitiveTypeKind.String) ||
TypeSemantics.IsPrimitiveType(parameterType, PrimitiveTypeKind.Binary))
{
int?size = GetParameterSize(parameterType, ((parameter.Direction & ParameterDirection.Output) == ParameterDirection.Output));
if (!size.HasValue)
{
// Remember the current Size
int previousSize = parameter.Size;
// Infer the Size from the value
parameter.Size = 0;
parameter.Value = value;
if (previousSize > -1)
{
// The 'max' length was chosen as a specific value for the parameter's Size property on Sql8 (4000 or 8000)
// because no MaxLength was specified in the TypeUsage and the provider is Sql8.
// If the value's length is less than or equal to this preset size, then the Size value can be retained,
// otherwise this preset size must be removed in favor of the Size inferred from the value itself.
// If the inferred Size is less than the preset 'max' size, restore that preset size
if (parameter.Size < previousSize)
{
parameter.Size = previousSize;
}
}
else
{
// -1 was chosen as the parameter's size because no MaxLength was specified in the TypeUsage and the
// provider is more recent than Sql8. However, it is more optimal to specify a non-max (-1) value for
// the size where possible, since 'max' parameters may prevent, for example, filter pushdown.
// (see Dev10#617447 for more details)
int suggestedLength = GetNonMaxLength(((SqlParameter)parameter).SqlDbType);
if (parameter.Size < suggestedLength)
{
parameter.Size = suggestedLength;
}
else if (parameter.Size > suggestedLength)
{
// The parameter size is greater than the suggested length, so the suggested length cannot be used.
// Since the provider is Sql9 or newer, set the size to max (-1) instead of the inferred size for better plan reuse.
parameter.Size = -1;
}
}
}
else
{
// Just set the value
parameter.Value = value;
}
}
else
{
// Not a string or binary parameter - just set the value
parameter.Value = value;
}
}
// <summary>
// Constructs a SqlCeParameter
// </summary>
internal static DbParameter CreateSqlCeParameter(
string name, TypeUsage type, object value, bool ignoreMaxLengthFacet, bool isLocalProvider)
{
var rdpSqlCeParameter = Type.GetType(RemoteProvider.SqlCeParameter);
// No other parameter type is supported.
//
DebugCheck.NotNull(type);
int? size;
byte?precision;
byte?scale;
var result = isLocalProvider
? new SqlCeParameter()
: (DbParameter)RemoteProviderHelper.CreateRemoteProviderType(RemoteProvider.SqlCeParameter);
result.ParameterName = name;
result.Value = value;
// .Direction
// parameter.Direction - take the default. we don't support output parameters.
result.Direction = ParameterDirection.Input;
// .Size, .Precision, .Scale and .SqlDbType
var sqlDbType = GetSqlDbType(type, out size, out precision, out scale);
// Skip guessing the parameter type (only for strings & blobs) if parameter size is not available
// Instead, let QP take proper guess at execution time with available details.
//
if ((null != size) ||
(!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.String) &&
!TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.Binary)))
{
if (isLocalProvider)
{
var sqlCeParameter = (SqlCeParameter)result;
if (sqlCeParameter.SqlDbType != sqlDbType)
{
sqlCeParameter.SqlDbType = sqlDbType;
}
}
else
{
// Remote Provider is loaded by reflection. As SqlDbType is not part of the base interface
// We need to access this using reflection only.
var rdpType = RemoteProviderHelper.GetRemoteProviderType(RemoteProvider.SqlCeParameter);
var rdpInfo = rdpType.GetProperty("SqlDbType");
rdpInfo.SetValue(result, sqlDbType, null);
}
}
// Note that we overwrite 'facet' parameters where either the value is different or
// there is an output parameter. This is because output parameters in SqlClient have their
// facets clobbered if they are implicitly set (e.g. if the Precision was implicitly set
// by setting the value)
if (!ignoreMaxLengthFacet &&
size.HasValue &&
(result.Size != size.Value))
{
result.Size = size.Value;
}
if (precision.HasValue &&
(((IDbDataParameter)result).Precision != precision.Value))
{
((IDbDataParameter)result).Precision = precision.Value;
}
if (scale.HasValue &&
(((IDbDataParameter)result).Scale != scale.Value))
{
((IDbDataParameter)result).Scale = scale.Value;
}
// .IsNullable
var isNullable = TypeSemantics.IsNullable(type);
if (isNullable != result.IsNullable)
{
result.IsNullable = isNullable;
}
return(result);
}
protected static void AssertBoolean(TypeUsage type)
{
Assert(
TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.Boolean), "Type Mismatch: Expected Boolean; found {0} instead",
type.ToString());
}
private void WriteFunctionElement(EdmFunction function)
{
_writer.WriteStartElement(function.IsFunctionImport ? XmlConstants.FunctionImport : XmlConstants.Function);
_writer.WriteAttributeString(XmlConstants.Name, function.Name);
// Write function ReturnType as attribute if possible.
bool returnParameterHandled = false;
if (function.ReturnParameter != null)
{
var returnTypeUsage = function.ReturnParameter.TypeUsage;
bool collection = returnTypeUsage.EdmType.BuiltInTypeKind == BuiltInTypeKind.CollectionType;
if (collection)
{
Debug.Assert(_schemaVersion >= EntityFrameworkVersions.Version3, "_schemaVersion >= EntityFrameworkVersions.Version3");
returnTypeUsage = ((CollectionType)returnTypeUsage.EdmType).TypeUsage;
}
if (TypeSemantics.IsPrimitiveType(returnTypeUsage) || TypeSemantics.IsNominalType(returnTypeUsage))
{
string typeName = GetFullName(returnTypeUsage.EdmType);
if (collection)
{
typeName = "Collection(" + typeName + ")";
}
_writer.WriteAttributeString(XmlConstants.ReturnType, typeName);
returnParameterHandled = true;
}
}
if (!_isModel)
{
_writer.WriteAttributeString(XmlConstants.AggregateAttribute, GetAttributeValueString(function.AggregateAttribute));
_writer.WriteAttributeString(XmlConstants.BuiltInAttribute, GetAttributeValueString(function.BuiltInAttribute));
_writer.WriteAttributeString(XmlConstants.NiladicFunction, GetAttributeValueString(function.NiladicFunctionAttribute));
_writer.WriteAttributeString(XmlConstants.IsComposable, GetAttributeValueString(function.IsComposableAttribute));
_writer.WriteAttributeString(XmlConstants.ParameterTypeSemantics, GetAttributeValueString(function.ParameterTypeSemanticsAttribute));
}
else if (function.IsFunctionImport && function.IsComposableAttribute)
{
Debug.Assert(_schemaVersion >= EntityFrameworkVersions.Version3, "_schemaVersion >= EntityFrameworkVersions.Version3");
_writer.WriteAttributeString(XmlConstants.IsComposable, GetAttributeValueString(true));
}
if (function.StoreFunctionNameAttribute != null)
{
_writer.WriteAttributeString(XmlConstants.StoreFunctionName, function.StoreFunctionNameAttribute);
}
if (function.CommandTextAttribute != null)
{
Debug.Assert(!_isModel, "Serialization of CommandTextAttribute is not supported for CSDL.");
_writer.WriteAttributeString(XmlConstants.CommandText, function.CommandTextAttribute);
}
if (function.Schema != null)
{
_writer.WriteAttributeString(XmlConstants.Schema, function.Schema);
}
foreach (FunctionParameter parameter in function.Parameters)
{
WriteFunctionParameterElement(parameter);
}
// Write function ReturnType subelement if needed.
if (function.ReturnParameter != null && !returnParameterHandled)
{
// Handle a TVF in s-space: Collection(RowType)
if (function.ReturnParameter.TypeUsage.EdmType.BuiltInTypeKind == BuiltInTypeKind.CollectionType)
{
Debug.Assert(_schemaVersion >= EntityFrameworkVersions.Version3 && !_isModel, "_schemaVersion >= EntityFrameworkVersions.Version3 && !_isModel");
var elementType = ((CollectionType)function.ReturnParameter.TypeUsage.EdmType).TypeUsage.EdmType;
Debug.Assert(elementType.BuiltInTypeKind == BuiltInTypeKind.RowType, "TVF return type is expected to be Collection(RowType)");
var rowType = (RowType)elementType;
_writer.WriteStartElement(XmlConstants.ReturnType);
_writer.WriteStartElement(XmlConstants.CollectionType);
WriteTypeElement(rowType);
_writer.WriteEndElement();
_writer.WriteEndElement();
returnParameterHandled = true;
}
}
Debug.Assert(function.ReturnParameter == null || returnParameterHandled, "ReturnParameter was not handled.");
_writer.WriteEndElement();
}
protected static void AssertBoolean(TypeUsage type)
{
Assert(TypeSemantics.IsPrimitiveType(type, PrimitiveTypeKind.Boolean), "Type Mismatch: Expected Boolean; found {0} instead", TypeHelpers.GetFullName(type));
}
internal DbOrExpression(TypeUsage booleanResultType, DbExpression left, DbExpression right)
: base(DbExpressionKind.Or, booleanResultType, left, right)
{
Debug.Assert(
TypeSemantics.IsPrimitiveType(booleanResultType, PrimitiveTypeKind.Boolean), "DbOrExpression requires a Boolean result type");
}
internal static DbExpression ConvertToString(ExpressionConverter parent, LinqExpression linqExpression)
{
if (linqExpression.Type == typeof(object))
{
var constantExpression = linqExpression as ConstantExpression;
linqExpression =
constantExpression != null?
Expression.Constant(constantExpression.Value) :
linqExpression.RemoveConvert();
}
var expression = parent.TranslateExpression(linqExpression);
var clrType = TypeSystem.GetNonNullableType(linqExpression.Type);
if (clrType.IsEnum)
{
//Flag enums are not supported.
if (Attribute.IsDefined(clrType, typeof(FlagsAttribute)))
{
throw new NotSupportedException(Strings.Elinq_ToStringNotSupportedForEnumsWithFlags);
}
if (linqExpression.IsNullConstant())
{
return(DbExpressionBuilder.Constant(string.Empty));
}
//Constant expression, optimize to constant name
if (linqExpression.NodeType == ExpressionType.Constant)
{
var value = ((ConstantExpression)linqExpression).Value;
var name = Enum.GetName(clrType, value) ?? value.ToString();
return(DbExpressionBuilder.Constant(name));
}
var integralType = clrType.GetEnumUnderlyingType();
var type = parent.GetValueLayerType(integralType);
var values = clrType.GetEnumValues()
.Cast <object>()
.Select(v => System.Convert.ChangeType(v, integralType, CultureInfo.InvariantCulture)) //cast to integral type so that unmapped enum types works too
.Select(v => DbExpressionBuilder.Constant(v))
.Select(c => (DbExpression)expression.CastTo(type).Equal(c)) //cast expression to integral type before comparing to constant
.Concat(new[] { expression.CastTo(type).IsNull() }); // default case
var names = clrType.GetEnumNames()
.Select(s => DbExpressionBuilder.Constant(s))
.Concat(new[] { DbExpressionBuilder.Constant(string.Empty) }); // default case
//translate unnamed enum values for the else clause, raw linq -> as integral value -> translate to cqt -> to string
//e.g. ((DayOfWeek)99) -> "99"
var asIntegralLinq = LinqExpression.Convert(linqExpression, integralType);
var asStringCqt = parent
.TranslateExpression(asIntegralLinq)
.CastTo(parent.GetValueLayerType(typeof(string)));
return(DbExpressionBuilder.Case(values, names, asStringCqt));
}
else if (TypeSemantics.IsPrimitiveType(expression.ResultType, PrimitiveTypeKind.String))
{
return(StripNull(linqExpression, expression, expression));
}
else if (TypeSemantics.IsPrimitiveType(expression.ResultType, PrimitiveTypeKind.Guid))
{
return(StripNull(linqExpression, expression, expression.CastTo(parent.GetValueLayerType(typeof(string))).ToLower()));
}
else if (TypeSemantics.IsPrimitiveType(expression.ResultType, PrimitiveTypeKind.Boolean))
{
if (linqExpression.IsNullConstant())
{
return(DbExpressionBuilder.Constant(string.Empty));
}
if (linqExpression.NodeType == ExpressionType.Constant)
{
var name = ((ConstantExpression)linqExpression).Value.ToString();
return(DbExpressionBuilder.Constant(name));
}
var whenTrue = expression.Equal(DbExpressionBuilder.True);
var whenFalse = expression.Equal(DbExpressionBuilder.False);
var thenTrue = DbExpressionBuilder.Constant(true.ToString());
var thenFalse = DbExpressionBuilder.Constant(false.ToString());
return(DbExpressionBuilder.Case(
new[] { whenTrue, whenFalse },
new[] { thenTrue, thenFalse },
DbExpressionBuilder.Constant(string.Empty)));
}
else
{
if (!SupportsCastToString(expression.ResultType))
{
throw new NotSupportedException(
Strings.Elinq_ToStringNotSupportedForType(expression.ResultType.EdmType.Name));
}
//treat all other types as a simple cast
return(StripNull(linqExpression, expression, expression.CastTo(parent.GetValueLayerType(typeof(string)))));
}
}