EqExpression class

Represents common expression object.

public abstract class Korzh.EasyQuery.EqExpression

Fields

Type	Name	Description
String	_text	This field contains expression’s text

Properties

Type	Name	Description
EntityAttr	Attribute	Gets or sets the attribute.
String	CustomFunc	Gets the custom func for expression if defined
DataType	DataType	Gets or sets the data type.
String	Hint	Gets or sets the expression hint.
Boolean	IsAggregate	Gets a value indicating whether this expression is aggregate.
DataKind	Kind	Gets the expression kind.
DataModel	Model	Gets the model.
Type	SystemType	Gets the system type for this expreesion (it’s used in LINQ query builder)
Int32	Tag	Get the expression’s tag - a special identifier that is used to distinguish the type of the expression .
String	Text	Gets or sets the expression text used for visual representation.
String	Value	Gets or sets the value of expression.

Events

Type	Name	Description
EventHandler	ContentChange	This event is raised after expression was changed

Methods

Type	Name	Description
void	AssignExpr(EqExpression expr)	Assigns some expression to this one. This method just does nothing in the base class but can perform some actions in Expression descendants.
void	ContentChanged()	Invoke ContentChange event
void	LoadFromXmlReader(XmlReader reader)	Loads expression from XML.
void	OnContentChange(EventArgs e)	Raises the ContentChange event.
void	ReadOnePropFromJson(JsonReader reader, String propName)	Reads one expression property from JSON.
Task	ReadOnePropFromJsonAsync(JsonReader reader, String propName)	Reads one expression property from JSON (asynchronous way).
void	SaveToXmlWriter(XmlWriter writer, String xmlTagName)	Saves expression to XML writer.
void	SaveToXmlWriter(XmlWriter writer)	Saves expression to XML writer.
void	SetContent(String val, String txt)	Sets the content of the expression (both its value and text).
void	SetContentSilent(String val, String txt)	Sets the content of the expression silently (without calling ContentChanged event).
String	TagToOldClassName(Int32 tag)	Converts the expression’s tag value to the name of old expression class (like “CONST” or “ENTATTR”).
void	WritePropertiesToJson(JsonWriter writer)	Writes all experssion properties to JSON. This method must be overriden in the descendant classes
Task	WritePropertiesToJsonAsync(JsonWriter writer)	Writes all experssion properties to JSON (asynchronous way). This method must be overriden in the descendant classes
void	WriteToJson(JsonWriter writer)	Write the content of the expression to JSON
Task	WriteToJsonAsync(JsonWriter writer)	Write the content of the expression to JSON (asynchronous way).
void	WriteXmlTagStart(XmlWriter writer)	Writes the expression XML tag start.
void	WriteXmlTagStart(XmlWriter writer, String tagName)	Writes the expression XML tag start.

Static Fields

Type	Name	Description
IList<IExpressionCreator>	Creators

Static Properties

Type	Name	Description
String	XmlTagName	Gets the name of the XML tag used for representation of Expression (an all its descendants) object in XML files.

Static Methods

Type	Name	Description
String	ApplyCustomFunc(String func, String expr)	Applies the custom function.
EqExpression	Create(DataModel model, Int32 tag)	Creates the expression instance of specified type.
EqExpression	CreateByClassName(DataModel model, String className)	Creates the expression instance of specified class (type) name.
EqExpression	ReadFromJson(DataModel model, JsonReader reader)	Reads one expression from JSON. This static function recognizes the expression type and creates an instance of appropriate class.
Task<EqExpression>	ReadFromJsonAsync(DataModel model, JsonReader reader)	Reads one expression from JSON.(asynchronous way). This static function recognizes the expression type and creates an instance of appropriate class.
Boolean	RegisterCreator(IExpressionCreator creator)	Registers new type of expression.