Is there a product that will kill grass and weeds without killing blooming flowers?

In my flower garden the weeds and grass have gotten out of control. Is there a product out there that I can use to kill those weeds and grasses without killing my flowers and plants?

Is there a product that will kill grass and weeds without killing blooming flowers?
Unfortunately not . Life would be a lot easier if you could.I would use a grass strimmer to whack the weeds down to ground level , then you would have a chance to use weedkiller without damaging the plants.If thats not practical you could always use a hoe.
Reply:Preen will not kill the grass and weeds, but will keep the seed from germinating AFTER you remove the existing plants, root and all.