jquery ui autocomplete match

I implemented jquery autocomplete ui on my page.. But when i search for example "am" every word which CONTAINS "am" is going to be listed in the drop down.

But i want just the words which BEGIN with "am" should be listed.

I dont know how to do that.. can you help me开发者_如何学C plz?

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Since you're getting the data from a serverside datasource, you should filter the data that is being returned to the autcomple control. The control will just show whatever data that is returned to it.