CrossFade broblem

HI guys,
I wanna know if there's a way to cut off CrossFade between animations.
For those of you who don't know CrossFade is a function which makes a dynamic transition between 2 animations by a given time, so my question is : is there a way to cut off this transition in the middle with crossfadeonfixedtime or something?
Thanks for all your help!

one way is to use to stop that crossfade,