(defun c:DTPLJOIN(/ AWS OLDCMD PLSSET)
  (vl-load-com)
  (if(and(or(setq AWS (ssget "_I" '((0 . "LINE,LWPOLYLINE,POLYLINE,ARC"))))
            (setq AWS (ssget      '((0 . "LINE,LWPOLYLINE,POLYLINE,ARC"))))
            (prompt "\nKeine Linien,Bögen, oder Polylinien gewählt")
         )         
     )
    (progn
      (setq OLDCMD (getvar "CMDECHO"))
      (setvar "CMDECHO" 0)
      (vla-endundomark  (vla-get-activedocument(vlax-get-acad-object)))
      (vla-startundomark(vla-get-activedocument(vlax-get-acad-object)))
      (setq INDEX -1)
      (repeat(sslength AWS)
        (if (not PLSSET)          
          (if(and(setq OBJ(ssname AWS (setq INDEX(1+ INDEX))))
                 (wcmatch (strcase(cdr(assoc 0(entget OBJ)))) "*POLYLINE")
             )
            (setq PLSSET OBJ)
          )
        )
      )
      (if(and(not(vl-catch-all-error-p
                  (vl-catch-all-apply
                    'vl-cmdf (cond                               
                               ((>(sslength AWS)1)(list "_pedit" "_m" AWS "" "_j" 0.5 ""))
                               ('T(list "_pedit" AWS ""))
                             )  
                  )
                 )
             )
             (setq AWS(if PLSSET (ssadd PLSSET)(ssadd(entlast))))
         )
        (progn
          (sssetfirst AWS AWS)
          (prompt "\nPolylinie erzeugt")
        )
        (prompt "\nFehler bei Polylinienerzeugung")
      )
      (vla-endundomark  (vla-get-activedocument(vlax-get-acad-object)))
      (setvar "CMDECHO" OLDCMD)
    )    
  )
  (princ)
)
(princ
  (strcat
    "\n\n"
    "\n[DT] PLJOIN: Zusammenfassen von Einzellinien zu Polylinien"
    "\n============ "
    "\n(C) Thomas Krüger 2010"     
    "\nBefehlszeilenaufruf : DTPLJOIN\n"
  )
)
(princ)