Add Custom and Extended Data¶

DXF supports storing custom data through various mechanisms.

Header Variables¶

Custom data can be stored in the HEADER section of a DXF file. Integer values are stored in variables named $USERI1 to $USERI5, while floating-point values are stored in variables named $USERR1 to $USERR5.

Example:

doc.header["$USERI1"] = 17

XDATA Section¶

The XDATA section is a container for extended data associated with an entity. It’s essentially a way to store additional information beyond the standard DXF properties for that particular entity. The XDATA section is divided into sub-sections, each associated with an AppID.

It’s important that the AppID is registered in the AppID table:

doc.appids.add("YOUR_ID")

ezdxf.sections.table.AppIDTable.add()

Example:

point = msp.add_point((10, 10))
point.set_xdata("YOUR_ID", (1040, 3.1415))

ezdxf.entities.DXFEntity.set_xdata()

Extension Dictionaries¶

Each DXF entity can have an extension dictionary to attach custom data. The extension dictionary is a Dictionary entity which stores references to other DXF entities in a key/value storage, mostly Dictionary and XRecord entities.

Example:

point = msp.add_point((10, 10))
xdict = point.new_extension_dict()

ezdxf.entities.DXFEntity.new_extension_dict()

Custom Data as XRECORD¶

The XRECORD is used to store arbitrary data. It is composed of DXF group codes ranging from 1 through 369. This object is similar in concept to XDATA but is not limited by size or order.

Example:

point = msp.add_point((10, 10))
xdict = point.new_extension_dict()
xrecord = xdict.add_xrecord("MyData")
xrecord.extend([(1, "MyText"), (40, 3.1415)])