关于parval

对parval()，属性指向很困扰
; C. `; H5 L1 d& F2 |+ {, X3 g比如： baynumber = parval(2)，求注解下，为什么是（2），

( T8 J. h8 r; e* s5 @* o: L& `0 Z如果levelnuber=?????  求注解。。。。
  W# R/ g3 A4 p2 y! x% p- [For developer use. This command is used inside a function that is called by the nodefunction() command. It returns the parameter passed to nodefunction specified by index as a number. The first additional parameter passed to nodefunction() is parameter 1, the second is parameter 2, etc. Parameters can also be retrieved using parnode() and parstr() for casting them as a treenode and string respectively.
Example: double passedval = parval(3);

% C: ]# Q7 V& m6 |# b* T% S( sThis sets passedval equal to the number that was passed to nodefunction() as parameter 3.

函数解释很详细哦他应该就是个传递参数吧