fun DateTimePicker.bind(property: ObservableValue<LocalDateTime>, readonly: Boolean = false) {
    ViewModel.register(valueProperty(), property)
    if (readonly || (property !is Property<*>)) valueProperty().bind(property) else valueProperty().bindBidirectional(property as Property<LocalDateTime>)
}
fun EventTarget.datetimepicker(op: DateTimePicker.() -> Unit = {}) = opcr(this, DateTimePicker(), op)
fun EventTarget.datetimepicker(property: Property<LocalDateTime>, op: DateTimePicker.() -> Unit = {}) = datetimepicker().apply {
    bind(property)
    op(this)
}