Topic: SubClass 100 values

[David Bethel]

Other than when required to included the SubClass 100 values in an (entmake), does anyone use the blasted things?

They've been around a while and I've seldom see them used ?

-David

[gile]

Hi,

These groups describe the inheritance relationship between classes. They can be used while inspecting a DXF list.

For example, the DXF list of an attribute reference:

Code - Text: [Select]

1. ((-1 . <Nom d 'entité: 7ffffb06a50>)
2.   (0 . "ATTRIB")
3.   (330 . <Nom d 'entité: 7ffffb06a40>)
4.   (5 . "1E45")
5.   (100 . "AcDbEntity")
6.   (67 . 0)
7.   (410 . "Model")
8.   (8 . "0")
9.   (62 . 0)
10.   (6 . "ByBlock")
11.   (370 . -2)
12.   (100 . "AcDbText")
13.   (10 129.005 313.129 0.0)
14.   (40 . 2.5)
15.   (1 . "test")
16.   (50 . 0.0)
17.   (41 . 1.0)
18.   (51 . 0.0)
19.   (7 . "Arial_std")
20.   (71 . 0)
21.   (72 . 4)
22.   (11 131.819 314.331 0.0)
23.   (210 0.0 0.0 1.0)
24.   (100 . "AcDbAttribute")
25.   (280 . 0)
26.   (2 . "ATT1")
27.   (70 . 8)
28.   (73 . 0)
29.   (74 . 0)
30.   (280 . 1)
31. )

The AcDbAttribute class inherits from the  AcDbText class which inherits from the AcDbEntity class (which inherits form AcDbObject).
Before the (100 . "AcDbEntity") are the common properties for all AcDbOject instances.
Between (100 . "AcDbEntity") and (100 . "AcDbText") are the AcDbEntiy specific properties which are common to all entities (all AcDbObject aren't entities i.e. layer, BlockTable, dictionaries...)
Between (100 . "AcDbText") and (100 . "AcDbAttribute") are the AcDbText specific properties (attribute definitions and attribute references, for example, inherit from AcDbText)
After (100 . "AcDbAttribute") are the attribute specific properties.

[David Bethel]

I've never seen the structure broken down in that way.  Very interesting.    :kewl:



But... Do you use it ?

[Lee Mac]

Great explanation gile, thanks