Ok, I've got this control I've made, and one of the most important factors to its success is speed. The fastest way to make something fast, in terms of knowing which item to pick from of a group, is to avoid searching and a whole lotta items for one particular need.

So, in short, I have an array of dates, and I want to know if a particular date is already within it without checking all of the separate values. How can I do this, or whats another way of doing the same thing?