drawing interchange and file formats(AutoCAD DXF 10.0版文件格式说明)

    enter decimal places of accuracy (0 to 16)/binary <6>:

c.1.2  dxfin command - loading a dxf file

a drawing interchange file can be converted into an autocad drawing by
means of the dxfin command.  first enter the drawing editor using the
"create new drawing" task from the main menu.  then issue the dxfin com-
mand.

    command:  dxfin   file name:  (name)

enter the name of the drawing interchange file to be loaded.

full dxfin

to load a complete dxf file, you must use dxfin in an empty drawing, before
any entities have been drawn and before any additional block definitions,
layers, linetypes, text styles, named views, named coordinate systems, or
named viewport configurations have been created.  (if your prototype draw-
ing contains any such items, use main menu task 1's "name=" technique to
create a new drawing without a prototype.)

if any errors are detected during the input, the new drawing is discarded.
otherwise, an automatic "zoom all" is performed to set the drawing extents.

partial dxfin

if the current drawing is not empty, dxfin loads only the entities section
of the dxf file, adding the entities found there to the current drawing.
in this case, dxfin displays the message:

    not a new drawing -- only entities section will be input.

if errors are detected during such partial dxf input, the drawing is
returned to the state it was in before the dxfin command.  otherwise, the
newly added entities are drawn.

2
                                   (c) drawing interchange and file formats

c.1.3  dxf file format

this section describes the format of a dxf file in detail.  it contains a
great deal of technical information that you need only if you're writing
your own program to process dxf files.  otherwise, you can skip this sec-
tion.

it would probably be helpful to produce a dxf file from a small drawing,
print it out, and refer to it occasionally while reading the information
presented below.

c.1.3.1  general file structure

a drawing interchange file is simply an ascii text file with a file type of
".dxf" and specially-formatted text.  the overall organization of a dxf
file is as follows:

  1. header section - general information about the drawing is found in
     this section of the dxf file.  each parameter has a variable name
     and an associated value.

  2. tables section -- this section contains definitions of named
     items.

       o  linetype (ltype) table
       o  layer table
       o  text style (style) table
       o  view table
       o  user coordinate system (ucs) table
       o  viewport configuration (vport) table
       o  drawing manager (dwgmgr) table (for future use)

  3. blocks section - this section contains block definition entities
     describing the entities comprising each block in the drawing.

  4. entities section - this section contains the drawing entities,
     including any block references.

  5. end of file

if you use dxfout's "entities" option, the resulting dxf file will contain
only the entities and end of file sections, and the entities section will
reflect only the objects you select for output.
本新闻共4页,当前在第2页  1  2  3  4