Substr

[andreas7ZYXQ]

I have a issue id like to solve.

In my substr i want to replace 16 with with pos..
i dont know how to get around it and make it work..

thanks.

(defun c:001 ()
 (setq plan "1");
 (setq pos "2")
 (setq name (getvar "dwgname"))
 (setq pos2 (substr name 16 1))
 ;(setq pos2 (substr name pos 1)) <---- someone that could give me some help and explain why it wint work? 
 (if (= plan pos2)
   (princ "This is true")
   (princ "This is false")
  );end of if statement
 );defun

[ВeekeeCZ]

your pos variable must be an INTEGER not a STRING 

(setq pos 2)

then for your father comparison must be plan an integer as well 

(defun c:001 ()
 (setq plan 1);
 (setq pos 2)
 (setq name (getvar "dwgname"))
 (setq pos2 (substr name 16 1))
 ;(setq pos2 (substr name pos 1)) <---- someone that could give me some help and explain why it wint work? 
 (if (= plan pos2)
   (princ "This is true")
   (princ "This is false")
  );end of if statement
 );defun

Read HERE about integers, real, strings... and conversions between them...

[john.uhden · Accepted solution]

How can (= plan pos2) ever be true?

plan is an integer, but pos2 is a string.

[ВeekeeCZ · Accepted solution]

---

@john.uhden wrote:

How can (= plan pos2) ever be true?

plan is an integer, but pos2 is a string.

---

Good point. Thx 

@andreas7ZYXQ Then keep your plan a string.

[andreas7ZYXQ]

I changed to this. Thanks alot for the advice @ВeekeeCZ

(defun c:001 ()
 (setq plan "1");
 (setq pos "2")
 (setq name (getvar "dwgname"))
(setq pos2 (substr name (atoi pos) 1))
 (if (= plan pos2)
   (princ "This is true")
   (princ "This is false")
  );end of if statement
 );defun