Basically to control what items are used by the DropDownList you need to use the dataSource objects and its methods.
In your case you will need to get reference to the client object and use the dataSource.data()
ds = $(
// make sure that the objects that you use to populate the dataSource have the same fields as the ones that you specified in the DataTextField and DataValueField of your DropDownList
I hope this helps.
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