正则表达式全球接受javascript中的后退空间

I've got this regex that I'm using to restrict currency fields and it works great because I can simply replace the . with a , and I can easily localize it on the fly. My only issues is I can't seem to delete the last remaining character using this regex and I would like to be able to do that. is there a way to modify this regex to allow that? I've got this regex that I'm using to restrict