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The result is a dynamic form that provides feedback to the user about which times are available.
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Note: This technique as it is here does not address simultaneous requests. Some additional code would be required to check that a slot is still available when the user clicks submit (in the situation where they opened the form and someone else submitted it before they did).
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Now our solution is more robust and can handle simultaneous users.
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The sample is attached, try it out!
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