merging arrays with jquery grep

I have two array ArrayA and ArrayB. Array B may have some values in it that belong to ArrayA. I'm looking to have ArrayB contain all the values of ArrayA. So far, th开发者_运维百科is is what I have:

for (i=0 ; i < ArrayB.length; i++)
{
  ArrayB = jQuery.grep(ArrayB, function (a) {
  ....
  };
};

I'm having some trouble with this function. Please let me know if you have any suggestions. Thanks.

---

ArrayB = jQuery.grep(ArrayB, function (a,i){
                   return jQuery.inArray(a, ArrayA) != -1;
         });