xdata codes

where can i find a list with all the possible XDATA codes and what type they accept?

Emmanuel

 

Hi Emmanuel

From Visual LISP Developer's Guide -> Using the AutoLISP Language -> Using
AutoLISP to Manipulate AutoCAD Objects -> Extended Data--xdata -> Organization
of Extended Data:

String
1000. Strings in extended data can be up to 255 bytes long (with the 256th byte
reserved for the null character).

Application Name
1001 (also a string value). Application names can be up to 31 bytes long (the
32nd byte is reserved for the null character) and must adhere to the rules for
symbol table names (such as layer names). An application name can contain
letters, digits, and the special characters $ (dollar sign), - (hyphen), and _
(underscore). It cannot contain spaces.

Layer Name
1003. Name of a layer associated with the xdata.

Database Handle
1005. Handle of an entity in the drawing database.

3D Point
1010. Three real values, contained in a point.

Real
1040. A real value.

Integer
1070. A 16-bit integer (signed or unsigned).

Long
1071. A 32-bit signed (long) integer. If the value that appears in a 1071 group
is a short integer or real value, it is converted to a long integer; if it is
invalid (for example, a string), it is converted to a long zero (0L).
Note:
AutoLISP manages 1071 groups as real values. If you use entget to retrieve an
entity's definition list that contains a 1071 group, the value is returned as a
real, as shown in the following example:
(1071 . 12.0)
If you want to create a 1071 group in an entity with entmake or entmod, you can
use either a real or an integer value, as shown in the following example:
(entmake '((..... (1071 . 12) .... )))
(entmake '((..... (1071 . 12.0) .... )))
(entmake '((..... (1071 . 65537.0) .... )))
(entmake '((..... (1071 . 65537) .... )))
But AutoLISP still returns the group value as a real:
(entmake '((..... (1071 . 65537) .... )))
The preceding statement returns the following:
(1071 . 65537.0)
ObjectARX always manages 1071 groups as long integers.

Several other extended data groups have special meanings in this context (if the
application chooses to use them):

Control String
1002. An xdata control string can be either "{" or "}". These braces enable the
application to organize its data by subdividing it into lists. The left brace
begins a list, and the right brace terminates the most recent list. Lists can be
nested.
Note:
If a 1001 group appears within a list, it is treated as a string and does not
begin a new application group.

Binary Data
1004. Binary data that is organized into variable-length chunks, which can be
handled in ObjectARX with the ads_binary structure. The maximum length of each
chunk is 127 bytes.
Note:
AutoLISP cannot directly handle binary chuncks, so the same precautions that
apply to long (1071) groups apply to binary groups as well.

World Space Position
1011. Unlike a simple 3D point, the WCS coordinates are moved, scaled, rotated,
and mirrored along with the parent entity to which the extended data belongs.
The WCS position is also stretched when the STRETCH command is applied to the
parent entity and when this point lies within the select window.

World Space Displacement
1012. A 3D point that is scaled, rotated, or mirrored along with the parent, but
not stretched or moved.

World Direction
1013. A 3D point that is rotated or mirrored along with the parent, but not
scaled, stretched, or moved. The WCS direction is a normalized displacement that
always has a unit length.

Distance
1041. A real value that is scaled along with the parent entity.

Scale Factor
1042. Also a real value that is scaled along with the parent.

Cheers

 

Hi Emmanuel

Forgot to mention some important additional points (missing in help):

1003: Layer name must exist in database
1005: Handle must exist in database
1071: since A2k also an Integer in LISP

Cheers

 

thanks Jürg !! very helpful!

 

Hi Emmanuel

Welcome... ¦-)

Cheers