IfcDocumentReference

IfcDocumentReference

实体定义

IfcDocumentReference是对文档位置的引用。引用由系统可解释的位置属性（URL字符串）和可选的继承内部引用标识给出，该属性指的是文档中的系统可解释位置。可选的继承名称属性对人类读者具有意义。可选的文档元数据也可以通过引用IfcDocumentInformation来捕获。

 

IFC2.0中的新实体

 

Formal Propositions

Rule	Description
WR1	A name should only be given, if no document information (including the document name) is attached

 

 

 

 

Attribute inheritance

#	Attribute	Type	Cardinality	Description	C
IfcExternalReference
1	Location	IfcURIReference	[0:1]	Location, where the external source (classification, document or library) can be accessed by electronic means. The electronic location is provided as an URI, and would normally be given as an URL location string.	X
2	Identification	IfcIdentifier	[0:1]	The Identification provides a unique identifier of the referenced item within the external source (classification, document or library). It may be provided as a key, e.g. a classification notation, like NF2.3 a handle a uuid or guid It may be human readable (such as a key) or not (such as a handle or uuid) depending on the context of its usage (which has to be determined by local agreement).	X
3	Name	IfcLabel	[0:1]	Optional name to further specify the reference. It can provide a human readable identifier (which does not necessarily need to have a counterpart in the internal structure of the document).	X
	ExternalReferenceForResources	IfcExternalReferenceRelationship @RelatingReference	S[0:?]	Reference to all associations between this external reference and objects within the IfcResourceObjectSelect that are tagged by the external reference.	X
IfcDocumentReference
4	Description	IfcText	[0:1]	Description of the document reference for informational purposes.	X
5	ReferencedDocument	IfcDocumentInformation	[0:1]	The document that is referenced.	X
	DocumentRefForObjects	IfcRelAssociatesDocument @RelatingDocument	S[0:?]	The document reference with which objects are associated.	X

 

 

EXPRESS Specification

ENTITY IfcDocumentReference
 SUBTYPE OF (IfcExternalReference);
  Description : OPTIONAL IfcText;
  ReferencedDocument : OPTIONAL IfcDocumentInformation;
 INVERSE
  DocumentRefForObjects : SET OF IfcRelAssociatesDocument FOR RelatingDocument;
 WHERE
  WR1 : EXISTS(Name) XOR EXISTS(ReferencedDocument);
END_ENTITY;

 

 

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标签：name,reference,IfcDocumentReference,external,IfcDocumentInformation,document
来源： https://www.cnblogs.com/herd/p/16645195.html