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Reformatting a Telephone Number

3:47 with Joel Kraft

Reformat the phone number users enter into the form. This will help them see at a glance whether they entered it correctly or not.

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    If they see it in a format they expect, 0:00
    it can help them know at a glance if it's correct or not. 0:00
    We want to do this reformatting when the user is completely done typing. 0:04
    The act the user takes when they're satisfied with the form input 0:08
    is to move focus away from the input. 0:12
    The blur event occurs on an input element when it loses focus. 0:15
    Let's use the blur event on this input to trigger our handler. 0:19
    I'll add a handler to the telephone input variable with addEventListener using 0:26

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