Idias needed

Attention ActiveX experts!
Here is a piece of my Detail_Block_Search program: "bks" - detail blocks collection from Detail_ Master drawing, "bpf" - detail block name prefix. When it's written this way:

(vlax-for dt bks
(if (and (= (vla-get-ObjectName dt) "AcDbBlockTableRecord")
(wcmatch (strcase (vla-get-name dt)) bpf));and
(print (vla-get-name dt))
))

it prints each Detail_Block Name once. But if it's written this way:
(vlax-for dt bks
(if (and (= (vla-get-ObjectName dt) "AcDbBlockTableRecord")
(wcmatch (strcase (vla-get-name dt)) bpf));and
(setq dtn (vla-get-name dt)) (print dtn)
))
it prints each Detail_Block Name several (up to 7) times.

Any ideas, why?
Thanks.

 

In your codes, the error comes with
(setq dtn (vla-get-name dt))
(print dtn)
if the condition is ok, run (setq dtn (vla-get-name dt))
or run (print dtn)
to force it run only once as u want, it should be
(vlax-for dt bks
(if (and (= (vla-get-ObjectName dt) "AcDbBlockTableRecord")
(wcmatch (strcase (vla-get-name dt)) bpf));and
(progn
(setq dtn (vla-get-name dt))
(print dtn)
)))