Algorithm to get changes between two arrays

Question

I needed to create an algorithm which will (efficiently) take an old array and a new array and give me back the changes between the two (which items added, which removed). It ha

Answer 1

The following page has a function that removes one array from another and can be used to give you the 2 values. Remove items from a JavaScript Array with RemoveArrayItems()

var newItemsAdded=RemoveArrayItems(oldArray,newArray);
var ItemsRemoved =RemoveArrayItems(newArray,oldArray);