• It stands for Drawing Exchange Format.
  • It is open source CAD file format.
  • It was developed by Autodesk in 1982.
  • DXF file format is a vector graphic file format.
  • It is used for sharing 2D and 3D drawings between Autocad and other programs.
  • The latest version supports both ASCII and binary forms.
       Representation of data using group codes and values:
  • Every variable in DXF file is associated with a group code.
  • Group codes ranging from 1 to 1071.
  • Group code 2 is used for names, such as names of blocks.
  • Group code 0 is refers to the start an entity or end of the file.
  • Values associated with each variable are stored as an integer, floating point or a string.

       File Structure:
  • Header:  Contains general information about the drawing. Each parameter has a variable name and an associated value.
  • Classes: Holds the information for application-defined classes whose instances appear in the BLOCKS, ENTITIES, and OBJECTS sections of the database. 
  • Tables: This section contains definitions of named items.
  • Application ID (APPID) table
  • Block Record (BLOCK_RECORD) table
  • Dimension Style (DIMSTYLE) table
  • Layer (LAYER) table  
      • Blocks: This section contains Block Definition entities describing the entities comprising each Block in the drawing.
      • Entities: This section contains the drawing entities, including any Block References.
      • Objects: Contains the data that apply to non graphical objects.
      • Thumb nail images:  Contains preview of images.
      • We can open DXF files with any text editor such as Notepad.
      • DXF editor:
      • DXF viewer:
      • Example: