Expression Class |
Expression class which defines field expressions which are
applied to fields in a select list, in update queries or in field predicates.
Valid expressions: FieldField ExOp FieldField ExOp ValueField ExOp ExpressionValue ExOp FieldValue ExOp ExpressionExpression ExOp FieldExpression ExOp Value Use one of the constructors to create the particular expression object.
Valid expressions: FieldField ExOp FieldField ExOp ValueField ExOp ExpressionValue ExOp FieldValue ExOp ExpressionExpression ExOp FieldExpression ExOp Value Use one of the constructors to create the particular expression object.
Inheritance HierarchyNamespace: SD.LLBLGen.Pro.ORMSupportClasses
Assembly: SD.LLBLGen.Pro.ORMSupportClasses (in SD.LLBLGen.Pro.ORMSupportClasses.dll) Version: 5.9.0.0 (5.9.0)
SyntaxThe Expression type exposes the following members.
Constructors| Name | Description | |
|---|---|---|
 | Expression |
CTor
|
| Expression(IEntityFieldCore) |
CTor for single field expressions.
|
 | Expression(SerializationInfo, StreamingContext) |
Initializes a new instance of the Expression class.
|
| Expression(Object, ExOp, IEntityFieldCore) |
CTor for value operator field expressions.
|
| Expression(Object, ExOp, IExpression) |
CTor for value operator (expression) expressions
|
| Expression(IEntityFieldCore, ExOp, IEntityFieldCore) |
CTor for field operator field expressions.
|
| Expression(IEntityFieldCore, ExOp, IExpression) |
CTor for field operator (expression) expressions.
|
| Expression(IEntityFieldCore, ExOp, Object) |
CTor for field operator value expressions.
|
| Expression(IExpression, ExOp, IEntityFieldCore) |
CTor for (expression) operator field expressions.
|
| Expression(IExpression, ExOp, IExpression) |
CTor for (expression) operator (expression) expressions.
|
| Expression(IExpression, ExOp, Object) |
CTor for (expression) operator value expressions.
|
Properties| Name | Description | |
|---|---|---|
 | DatabaseSpecificCreator |
Object which will be used to create valid parameter objects, field names, including prefix/postfix characters,
and conversion routines, and field names, including prefix/postfix characters.
Uses the strategy pattern so the generic code can work with more than one target database.
|
| LeftOperand |
Gets the left expression operand. Set by the constructor used.
|
| Operator |
Gets the operator of the expression. Not valid (ExOp.None) if RightOperand is null. Set by the constructor used.
|
| Parameters |
The list of parameters created when the Expression was translated to text usable in a query. Only valid after a succesful call to ToQueryText
|
| RightOperand |
Gets the right expression operand. Set by the constructor used.
Can be null
|
Methods| Name | Description | |
|---|---|---|
| ConvertObjectOperandToExpressionElement |
Converts the object operand to expression element.
|
| Equals | Determines whether the specified object is equal to the current object. (Inherited from Object.) |
| Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
| GetHashCode | Serves as the default hash function. (Inherited from Object.) |
| GetObjectData |
Populates a SerializationInfo with the data needed to serialize the target object.
|
| GetType | Gets the Type of the current instance. (Inherited from Object.) |
| MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
| OperandToValue |
Resolves the passed in operand to its value at runtime.
|
| PerformGetValue |
Produces the value for this expression for the entity passed in. This routine is used by IExpressionInterpret.GetValue and is used
to evaluate an expression at runtime for in-memory filtering/sorting.
|
| ToQueryText |
Retrieves a ready to use text representation of the contained expression.
|
| ToQueryText(Boolean) |
Retrieves a ready to use text representation of the contained expression.
|
| ToString | Returns a string that represents the current object. (Inherited from Object.) |
Operators| Name | Description | |
|---|---|---|
  | Addition(Object, Expression) |
Operator overload for the '+' operator to produce an Expression which represents value + expression
|
| Addition(Expression, Expression) |
Operator overload for the '+' operator to produce an Expression which represents expression + expression
|
| Addition(Expression, Object) |
Operator overload for the '+' operator to produce an Expression which represents expression + value
|
| Division(Object, Expression) |
Operator overload for the '/' operator to produce an Expression which represents value / expression
|
| Division(Expression, Expression) |
Operator overload for the '/' operator to produce an Expression which represents expression / expression
|
| Division(Expression, Object) |
Operator overload for the '/' operator to produce an Expression which represents expression / value
|
| Multiply(Object, Expression) |
Operator overload for the '*' operator to produce an Expression which represents value * expression
|
| Multiply(Expression, Expression) |
Operator overload for the '*' operator to produce an Expression which represents expression * expression
|
| Multiply(Expression, Object) |
Operator overload for the '*' operator to produce an Expression which represents expression * value
|
| Subtraction(Object, Expression) |
Operator overload for the '-' operator to produce an Expression which represents value - expression
|
| Subtraction(Expression, Expression) |
Operator overload for the '-' operator to produce an Expression which represents expression - expression
|
| Subtraction(Expression, Object) |
Operator overload for the '-' operator to produce an Expression which represents expression - value
|
Extension Methods| Name | Description | |
|---|---|---|
 | Add |
Creates a new expression: leftoperand + rightoperand
(Defined by ExpressionExtensionMethods.) |
| AddDays |
Defines the mapping for the expression.AddDays(numberOfDays) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| AddHours |
Defines the mapping for the expression.AddHours(numberOfHours) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| AddMilliseconds |
Defines the mapping for the expression.AddMilliseconds(numberOfMilliseconds) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| AddMinutes |
Defines the mapping for the expression.AddMinutes(numberOfMinutes) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| AddMonths |
Defines the mapping for the expression.AddMonths(numberOfMonths) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| AddSeconds |
Defines the mapping for the expression.AddSeconds(numberOfSeconds) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| AddYears |
Defines the mapping for the expression.AddYears(numberOfYears) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| And |
Creates a new expression: leftoperand AND rightoperand
(Defined by ExpressionExtensionMethods.) |
| As |
Specifies the specified alias on the expression specified.
(Defined by ExpressionExtensionMethods.) |
| Ascending |
Creates an ascending sort clause for the expression specified
(Defined by SortClauseProducers.) |
| Avg |
Places the Avg aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| AvgDistinct |
Places the Avg(Distinct) aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| Between |
Creates a Between predicate which is true if the result of the expression specified is between valueBegin and valueEnd, valueBegin and valueEnd included.
(Defined by BetweenPredicateProducers.) |
| BitwiseAnd |
Creates a new expression: leftoperand BitwiseAnd rightoperand
(Defined by ExpressionExtensionMethods.) |
| BitwiseOr |
Creates a new expression: leftoperand BitwiseOr rightoperand
(Defined by ExpressionExtensionMethods.) |
| BitwiseXor |
Creates a new expression: leftoperand BitwiseXor rightoperand
(Defined by ExpressionExtensionMethods.) |
| CastToTResult |
Specifies the result type of the expression to be TResult
(Defined by ExpressionExtensionMethods.) |
| Char |
Defines the mapping for the expression.Char[index] property to method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Contains(String) | Overloaded.
Creates a Like predicate using the pattern: '%pattern%' for the expression specified.
(Defined by StringMethodPredicateProducers.) |
| Contains(String, NullableChar) | Overloaded.
Creates a Like predicate using the pattern: '%pattern%' for the expression specified.
(Defined by StringMethodPredicateProducers.) |
| Count |
Places the Count aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| CountBig |
Places the CountBig aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| CountBigDistinct |
Places the CountBig(Distinct) aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| CountDistinct |
Places the Count(Distinct) aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| Date |
Defines the mapping for the expression.Date property to method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Day |
Defines the mapping for the expression.Day property to method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Descending |
Creates a descending sort clause for the expression specified
(Defined by SortClauseProducers.) |
| Div |
Creates a new expression: leftoperand / rightoperand
(Defined by ExpressionExtensionMethods.) |
| EndsWith |
Creates a Like predicate using the pattern: '%pattern' for the expression specified.
(Defined by StringMethodPredicateProducers.) |
| Equal(Object) | Overloaded.
Creates an equality comparison predicate between the expression and the value specified. If the value is null or DBNull.Value a null comparison predicate is created
(Defined by EqualOpPredicateProducers.) |
| Equal(IEntityFieldCore) | Overloaded.
Creates an equality comparison predicate between the expression and the field specified.
(Defined by EqualOpPredicateProducers.) |
| Equal(IExpression) | Overloaded.
Creates an equality comparison predicate between the two expressions specified.
(Defined by EqualOpPredicateProducers.) |
| GreaterEqual(Object) | Overloaded.
Creates a greater or equal comparison predicate between the expression and the value specified. If the value is null or DBNull.Value a null comparison predicate is created
(Defined by GreaterEqualOpPredicateProducers.) |
| GreaterEqual(IEntityFieldCore) | Overloaded.
Creates a greater or equal comparison predicate between the expression and the field specified.
(Defined by GreaterEqualOpPredicateProducers.) |
| GreaterEqual(IExpression) | Overloaded.
Creates a greater or equal comparison predicate between the two expressions specified.
(Defined by GreaterEqualOpPredicateProducers.) |
| GreaterThan(Object) | Overloaded.
Creates a greater than comparison predicate between the expression and the value specified. If the value is null or DBNull.Value a null comparison predicate is created
(Defined by GreaterThanOpPredicateProducers.) |
| GreaterThan(IEntityFieldCore) | Overloaded.
Creates a greater than comparison predicate between the expression and the field specified.
(Defined by GreaterThanOpPredicateProducers.) |
| GreaterThan(IExpression) | Overloaded.
Creates a greater than comparison predicate between the two expressions specified.
(Defined by GreaterThanOpPredicateProducers.) |
| Hour |
Defines the mapping for the expression.Hour property to method mapping
(Defined by FunctionMappingExtensionMethods.) |
| In(Object) | Overloaded.
Creates a Field IN (values) predicate
(Defined by InPredicateProducers.) |
| In(DynamicQuery) | Overloaded.
Creates a Field IN (query) predicate
(Defined by InPredicateProducers.) |
| IndexOf |
Defines the mapping for the expression.IndexOf(value) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| IsNotNull |
Generates a negated FieldCompareNull predicate on the expression specified.
(Defined by IsNullPredicateProducers.) |
| IsNull |
Generates a FieldCompareNull predicate on the expression specified.
(Defined by IsNullPredicateProducers.) |
| Length |
Defines the mapping for the expression.Length property to method mapping, if expression represents a string value.
(Defined by FunctionMappingExtensionMethods.) |
| LesserEqual(Object) | Overloaded.
Creates a lesser or equal comparison predicate between the expression and the value specified. If the value is null or DBNull.Value a null comparison predicate is created
(Defined by LesserEqualOpPredicateProducers.) |
| LesserEqual(IEntityFieldCore) | Overloaded.
Creates a lesser or equal comparison predicate between the expression and the field specified.
(Defined by LesserEqualOpPredicateProducers.) |
| LesserEqual(IExpression) | Overloaded.
Creates a lesser or equal comparison predicate between the two expressions specified.
(Defined by LesserEqualOpPredicateProducers.) |
| LesserThan(Object) | Overloaded.
Creates a lesser than comparison predicate between the expression and the value specified. If the value is null or DBNull.Value a null comparison predicate is created
(Defined by LesserThanOpPredicateProducers.) |
| LesserThan(IEntityFieldCore) | Overloaded.
Creates a lesser than comparison predicate between the expression and the field specified.
(Defined by LesserThanOpPredicateProducers.) |
| LesserThan(IExpression) | Overloaded.
Creates a lesser than comparison predicate between the two expressions specified.
(Defined by LesserThanOpPredicateProducers.) |
| Like |
Creates a Like predicate for the expression specified using the pattern specified. The pattern has to contain the wildcards required.
(Defined by StringMethodPredicateProducers.) |
| Max |
Places the Max aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| Millisecond |
Defines the mapping for the expression.Millisecond property to method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Min |
Places the Min aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| Minute |
Defines the mapping for the expression.Minute property to method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Mod |
Creates a new expression: leftoperand MOD rightoperand
(Defined by ExpressionExtensionMethods.) |
| Month |
Defines the mapping for the expression.Month property to method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Mul |
Creates a new expression: leftoperand * rightoperand
(Defined by ExpressionExtensionMethods.) |
| NotBetween |
Creates a Between predicate which is true if the result of the expression specified is not between valueBegin and valueEnd, valueBegin and valueEnd included.
(Defined by BetweenPredicateProducers.) |
| NotEqual(Object) | Overloaded.
Creates a negated equality comparison predicate between the expression and the value specified. If the value is null or DBNull.Value a null comparison predicate is created
(Defined by NotEqualOpPredicateProducers.) |
| NotEqual(IEntityFieldCore) | Overloaded.
Creates a negated equality comparison predicate between the expression and the field specified.
(Defined by NotEqualOpPredicateProducers.) |
| NotEqual(IExpression) | Overloaded.
Creates a negated equality comparison predicate between the two expressions specified.
(Defined by NotEqualOpPredicateProducers.) |
| NotIn(Object) | Overloaded.
Creates a NOT (Field IN (values)) predicate
(Defined by InPredicateProducers.) |
| NotIn(DynamicQuery) | Overloaded.
Creates a NOT (Field IN (query)) predicate
(Defined by InPredicateProducers.) |
| Or |
Creates a new expression: leftoperand Or rightoperand
(Defined by ExpressionExtensionMethods.) |
| Replace |
Defines the mapping for the expression.Replace(oldValue, newValue) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Second |
Defines the mapping for the expression.Second property to method mapping
(Defined by FunctionMappingExtensionMethods.) |
| StartsWith |
Creates a Like predicate using the pattern: 'pattern%' for the expression specified.
(Defined by StringMethodPredicateProducers.) |
| StDev |
Places the StDev aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| StDevDistinct |
Places the StDev(Distinct) aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| Sub |
Creates a new expression: leftoperand - rightoperand
(Defined by ExpressionExtensionMethods.) |
| Substring(Int32) | Overloaded.
Defines the mapping for the expression.Substring(startIndex) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Substring(Int32, Int32) | Overloaded.
Defines the mapping for the expression.Substring(startIndex, length) method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Sum |
Places the Sum aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| SumDistinct |
Places the Sum(Distinct) aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| ToLower |
Defines the mapping for the expression.ToLower() method mapping
(Defined by FunctionMappingExtensionMethods.) |
| ToUnicode |
Defines the mapping for the expression.ToUnicode() method mapping
(Defined by FunctionMappingExtensionMethods.) |
| ToUpper |
Defines the mapping for the expression.ToUpper() method mapping
(Defined by FunctionMappingExtensionMethods.) |
| ToValueTValue |
Placeholder method which is used in a Select(lambda func) projection inside the lambda to specify the type of the result of the passed in expression.
(Defined by ExpressionExtensionMethods.) |
| Trim |
Defines the mapping for the expression.Trim() method mapping
(Defined by FunctionMappingExtensionMethods.) |
| Variance |
Places the Variance aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| VarianceDistinct |
Places the Variance(Distinct) aggregate function on the expression specified and returns a wrapping field with the expression.
(Defined by AggregateRelatedExtensionMethods.) |
| Year |
Defines the mapping for the expression.Year property to method mapping
(Defined by FunctionMappingExtensionMethods.) |
Explicit Interface Implementations| Name | Description | |
|---|---|---|
  | IXmlSerializableGetSchema |
This method is reserved and should not be used. When implementing the IXmlSerializable interface, you should return null (Nothing in Visual Basic) from this method, and instead, if specifying a custom schema is required, apply the XmlSchemaProviderAttribute to the class.
|
| IXmlSerializableReadXml |
Generates an object from its XML representation.
|
| IXmlSerializableWriteXml |
Converts an object into its XML representation.
|
| IExpressionReadXml |
Deserializes the data on the xml reader into an expression instance
|
| IExpressionWriteXml |
Serializes object as xml to the writer specified.
|
| IExpressionInterpretGetValue |
Interprets the implementing expression class on the passed in entity.
|
RemarksValues are transformed into parameters. The type of the parameter is determined of the field in the expression.
You can also use EntityProperty instances instead of EntityField(2) instances, though the Expression instance then has to be used solely for in-memory actions.
You can also use EntityProperty instances instead of EntityField(2) instances, though the Expression instance then has to be used solely for in-memory actions.
See Also