This took me an age to track down. How do you get the value out of the UIDatePicker that the user has selected. Having used UIPickerViews a lot, I thought that UIDatePicker object would have been an extension of UIPickerView and with the same methods, however this turned out not to be the case and the solution for UIDatePicker was much more straight forward.
[pickerObject date]; //where pickerObject is the name of your date picker object
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