acedCommand()函数的限制:
The following restrictions apply to this function:
You cannot call acedCommand() to invoke AutoLISP functions nor other ARX applications (external functions in other ARX applications can be invoked with acedInvoke()).
You cannot call acedCommand() to invoke AutoCAD commands that directly access peripheral devices. These commands include DTEXT, SKETCH, and PLOT.
You can call acedCommand() to invoke SCRIPT or RSCRIPT (unlike the AutoLISP (command)).
引自: arxref.chm