No system is perfect. Eventually, you will encounter a file that is corrupted in some way. AutoCAD offers two tools that can frequently salvage a corrupted file: Audit and Recover.Audit allows you to check a file that you are able to open, but you suspect has some problem. Recover allows you to open a file that is so badly corrupted that Auto- CAD is unable to open it in a normal way. You can access these tools from the File >-Drawing Utilities cascading menu. The functions of these options are as follows:
Audit, Checks the current file for any errors and displays the results in the text window.
Recover Attempts to recover damaged or corrupted AutoCAD files. The current file is closed in the process as Recover attempts to open the file to be recovered.
More often than not, these tools will do the job, although they aren’t a panacea for all file corruption problems. In the event that you cannot recover a file even with these tools, make sure your computer is running smoothly and that other systems are not faulty.
Exchanging CAD-Data with Other Programs
AutoCAD offers many ways to share data with other programs. Perhaps the most common type of data exchange is simply to share drawing data with other CAD programs. In this section, you’ll look at how you can export and import CAD drawings using the .dxf file format. You’ll also look at how you can use bitmap graphics, both to and from AutoCAD, through the Windows Clipboard.
Other types of data exchange involve text, spreadsheets, and databases. Chapter 10 covers database links, but this section will describe how you can include text, spreadsheet, and database files in a drawing or include AutoCAD drawings in other program files using a Windows feature called Object Linking and Embedding (OLE).
Using the .dxf File Format
A .dxf file is a OOS text file containing all the information needed to reconstruct a drawing. It is often used to exchange drawings created with other programs. Many micro-CAD programs, including some 3D perspective programs, can generate or read files in .dxf format. You may want to use a 3D program to view your drawing in a Perspective view, or you may have a consultant who uses a different CAD program that accepts .dxf files. There are many 3D rendering programs that read .dxf files, on both Windows and Macintosh !np~ters. Most 2D drafting programs also read and write .dxf files
Be aware that not all programs that read .dxf files will accept all the data stored therein. Many programs that claim to read .dxf files will “throw away” much of the .dxf file’s information. Attributes are perhaps the most commonly ignored objects, followed by many of the 3D objects, such as meshes and 3D Faces. But .dxf files, though not the most perfect medium for translating data, have become something of a standard.
Exporting .dxf Files
To export your curre~t drawing as a .dxf file, try the following exercise:
1. Choose Pile >Save As. The Save Drawing As dialog box appears.
2 Click the Save as Type drop-down list. You have the option to export your drawing under a number of formats, including four different .dxf formats.
3. Select the appropriate .dxf format, and then enter a name for your file. You do not have to include the .dxf filename extension.
4. Select a folder for the file, and then click Save.
In step 2, you can select from the following .dxf file formats:
• AutoCAD 2000DXF
• AutoCAD R14DXF
• AutoCAD R13/LT95 DXF
• AutoCAD R12/LT2 DXF
Choose the format appropriate to the program you are exporting to. In most cases, the safest choice is AutoCAD Rl2/LT2 DXFif you are exporting to another CAD program, though AutoCAD will not maintain the complete functionality of AutoCAD 2000 for such files. .
Once you’ve selected a .dxf format from the Save as Type drop-down list, you can set more detailed specifications by clicking the Options button it). the Save Drawing As dialog box. Doing so opens the Save as Options dialog box. For DXF files, select the DXFOptions tab. This is what it looks like.
Format Lets you choose between ASCII (plain text) or binary file formats. Most other programs accept ASCII, so it is the safest choice. Some programs.
accept binary .dxf files, which have the advantage of being more compact than the ASCII format.
Select Objects Lets you select specific objects within the drawing for export. You have the option to select objects after you have dosed the Export
Options dialog box and selected Save from the Export Data dialog box. Save Thumbnail Preview Image Lets you save an image with the file so the you use the AutoCAD ile >- Open option; you can see a preview image of the DXF file.
Decimal Places of Accuracy Allows you to determine the accuracy of the exported file. Keeping this value low helps reduce the size of the export file, particularly if it is to be in the ASCII format. Some CAD programs do not support the high accuracy of AutoCAD, so using a high value here may have no significance.
Opening or Importing .dxf Files
Some offices have standardized their CAD drawings on the .dxf file format. This is most commonly seen in offices that use a variety of CAD software besides Auto- D. AutoCAD 2000 can be set up to read and write DXF files by default, instead of the standard DWG file format. Here’s how it’s done.
1. Choose Tools >- Options to open the Options dialog box.
2. Select the Open and Save tab.
3. Select from any of the DXF formats from the Save As drop-down list
4. Click OK.
Once you do this, all of your drawings are automatically saved in the DXF format of your choice. AutoCAD also displays DXF files in the File dialog box when you choose File >- Open.
You can also set the default AutoCAD file type by clicking the Options button in the Save Drawing As dialog box. As you saw in an earlier section, the Save as
Options dialog box offers DWG Options. You can select a default file type from the Save All Drawings As drop-down list.
If you just need to open a DXF file once in a while, you can do so by selecting DXF from the File of Type drop-down list in the Select File dialog box, This is the dialog box you see when you choose File >- Open. You can also import .dxf files into the current open file, provided that the .dxf file does not contain blocks or other named elements that do not exist in the current file:
1. Type Dxfin.J at the command prompt. The Select .DXF File dialog box appears. This is a typical Windows file dialog box.
2. Locate and select the .dxf file you wish to import.
3. Double-click the filename to begin importing it.
If the import drawing is large, AutoCAD may take several minutes to import it