Topic: Trying to get filename to use but there is error

[HasanCAD]

I am trying to use file name as a prefix but when press enter result is not the filename

Thanks

Code - Auto/Visual Lisp: [Select]

1. (setq filepath (getvar "dwgname"))
2. (setq filename (VL-FILENAME-BASE filepath))
3.  
4. (setq fileprefix
5.        (cond ((getstring (strcat "\nEnter filename prefix: < "
6.                                  (setq fileprefix
7.                                         (cond (fileprefix)
8.                                               (filename)
9.                                         )
10.                                  )
11.                                  " >?: "
12.                          )
13.               )
14.              )
15.              (fileprefix)
16.        )
17. )

The result is

""

[Keith™]

Check DWGTITLED
If it is 0 no path is included in DWGNAME

[Dlanor]

Your condition (cond) is incorrect

Perhaps

Code - Auto/Visual Lisp: [Select]

1.  
2.     (setq filepath (getvar "dwgname"))
3.     (setq filename (VL-FILENAME-BASE filepath))
4.      
5.     (setq fileprefix
6.       (cond ( (getstring (strcat "\nEnter filename prefix: < " (setq fileprefix (if (not fileprefix) filename)) " >?: ")))
7.             (t fileprefix)
8.       )
9.     )
10.  
11.  
12.  

[HasanCAD]

Thanks Keith

Thanks Dlaner but gives the same result
In command line shows the filename but when click Enter gives this

Code: [Select]

"222-Layout2.dwg"
"222-Layout2"
""

[Dlanor]

What are you expecting to get?

[Keith™]

Upon closer examination, the whole issue is with COND and getstring and the evaluation order.

Consider this:

Code - Auto/Visual Lisp: [Select]

1.     (setq fileprefix ;;THIS IS THE SECOND TIME fileprefix IS SET TO A VALUE
2.         (cond ;; this designates that there are several conditions to test against
3.             ;; Begin COND1
4.             (
5.                  ;;CAPTURE USER INPUT
6.                  (getstring
7.                       ;;USING A CONCATENATED STRING PROMPT
8.                       (strcat
9.                             "\nEnter filename prefix: < " ;;WITH THIS STRING
10.                              ;; PLUS THE RETURN VALUE OF THIS EVALUATION
11.                              (setq fileprefix ;;THIS IS THE FIRST TIME fileprefix IS SET TO A VALUE
12.                                    ;;IF WE DON'T HAVE A FILENAME WITHOUT EXTENSION
13.                                    (if (not fileprefix)
14.                                          ;;JUST USE THE FILENAME WITH EXTENSION  
15.                                          filename)
16.                               );; END SETQ
17.                                " >?: " ;;AND THIS STRING TO BUILD OUR PROMPT
18.                       );; END STRCAT
19.                  );; END GETSTRING
20.             );;END COND1
21.             ;;BEGIN COND2 - FAILOVER RETURN fileprefix to user
22.             ;;This code will never be executed because getstring will always pause
23.             ;;and wait for user input. pressing enter at getstring prompt returns
24.             ;;returns an empty string thus fulfilling the COND as it is NOT NIL
25.             (t fileprefix)
26.         );;END COND
27.     );;END SETQ

Of course the fix is rather simple:

Code - Auto/Visual Lisp: [Select]

1.     ;;corrections in CAPITALS
2.     (setq fileprefix
3.         (cond
4.             ((getstring (strcat "\nEnter filename prefix: < "(setq fileprefix (if (not fileprefix) filename FILEPREFIX)) " >?: " )) FILEPREFIX)
5.             (t fileprefix)
6.         )
7.     )

All that being said, a COND is really unnecessary, but it does work

[roy_043]

The getstring function will return "" instead of nil if the user presses Enter.

Code - Auto/Visual Lisp: [Select]

1. (setq filepath (getvar "dwgname"))
2. (if (not fileprefix) (setq fileprefix (vl-filename-base filepath)))
3. (if (/= "" (setq tmp (getstring (strcat "\nEnter filename prefix: < " fileprefix " >?: "))))
4.   (setq fileprefix tmp)
5. )

[HasanCAD]

Code - Auto/Visual Lisp: [Select]

1. ;;corrections in CAPITALS
2.     (setq fileprefix
3.         (cond
4.             ((getstring (strcat "\nEnter filename prefix: < "(setq fileprefix (if (not fileprefix) filename FILEPREFIX)) " >?: " )) FILEPREFIX)
5.             (t fileprefix)
6.         )
7.     )

Thanks Working perfect

[roy_043]

Thanks Working perfect

Are you sure?
Keith's code completely ignores the getstring user input.

[Keith™]

Thanks Working perfect

Are you sure?
Keith's code completely ignores the getstring user input.

You are correct

His initial problem was that pressing enter in GETSTRING returns an empty string thus an empty string was always returned.
Pressing enter will now return the name of the drawing, however, it will not return the value captured by GETSTRING because it is never stored.

In order to resolve this issue, the function would need to be altered.

I wouldn't have attempted to write it in this manner.

I would have written it something like this:

Code - Auto/Visual Lisp: [Select]

1. (defun c:test (/ fn pr pf)
2.   (setq fn (vl-filename-base (getvar "dwgname")))
3.   (setq pr (strcat "\nEnter filename prefix: < " fn " >?: "))
4.   (setq pf (getstring pr))
5.   (if (= pf "")
6.     (setq pf fn)
7.   )
8.   pf
9. )