[编程交流] 需要的值，输入忽略

Establishes limitations on the user responses allowed by the next get- function
(initget 1) null input not allowed ("null input" means 'Enter' by itself)
(initget 2) 0 input not allowed
(initget 3) null input and 0 input not allowed (3 = 1 + 2)
(initget 4) negative values not allowed
(initget 5) null input and negative values not allowed (5 = 1 + 4)
(initget 6) 0 input and negative values not allowed (6 = 2 + 4)
(initget 7) null input, 0 input, and negative values not allowed (7 = 1 + 2 + 4)
(initget  cancels limits check
(initget 16) (not used)
(initget 32) causes get- functions that include a base point to display a rubber band cursor or window that is highlighted rather than solid
(initget 64) Z coordinate not allowed in next getdist function
(initget 128) allows arbitrary input (accepts any "key word")
(initget "A B C") allows the user to enter "A" "B" "C" "a" "b" or "c" in response to the next get- function (in addition, of course, to the possibility of entering an integer if the next get- function is getint, a real if it is getreal, etc.) Subsequent programming must be set up to handle these strings.

(if (setq Input (getdist "\nLength of First Peice: " ))(setq pcs1 Input))
(if (setq Input (getdist "\nLength of Second Peice: "))(setq pcs2 Input))
(if (setq Input (getdist "\nLength of Third Peice: " ))(setq pcs3 Input))

(or pcs1 (setq pcs1 10.0))
(if
 (setq Input (getdist (strcat "\nLength of First Peice [" (rtos  pcs1) "] : " )))
 (setq pcs1 Input))

(setq pcs1 (cond ((getdist "\nLength of First Peice <10.0>: "))
                (10.0)
          )
)

(setq *pcs1* (cond ((getdist (strcat "\nLength of First Peice <"
                                    (rtos (cond (*pcs1*)
                                                ((setq *pcs1* 10.0))
                                          )
                                    )
                                    ">: "
                            )
                   )
                  )
                  (*pcs1*)
            )
)