У меня есть форма с выбранными полями, как показано ниже.
Мне нужно сгруппировать первые два поля выбора «Выбрать сеанс» и «Выбрать время», мне нужно разрешить выбирать уникальные сеансы и время для каждой пары раскрывающихся списков.Если я выбрал один сеанс и время в одном раскрывающемся списке, и снова я выбрал тот же сеанс и время в нижеприведенных выпадающих сообщениях, тогда мне нужно будет отобразить сообщение об ошибке, например «Тот же сеанс и время уже выбрано».
Как я могу это сделать? .. HTML-код
<div class="line_div">
<p>You can enroll in one or more sessions:</p>
<div class="sgl_part_div">
<span class="cmt">Select Session</span><span>:</span>
<select id="first" name="first" class="tx_bx" value="">
<option value="">- Select -</option>
<option value="">Session #1: Tues May 31st - Fri June 10th (1-5:30PM)</option>
<option value="">Session #2: Tues June 14th - Fri June 24th (9-2:00PM)</option>
<option value="">Session #3: Tues June 28th - Fri July 8th (9-2:00PM)</option>
<option value="">Session #4: Tues July 12th - Fri July 22nd (9-2:00PM)</option>
<option value="">Session #5: Tues July 26th - Fri Aug 5th (9-2:00PM)</option>
<option value="">Session #6: Tues Aug 9th - Fri Aug 19th (9-2:00PM)</option>
</select>
</div>
<div class="sgl_part_div">
<span class="cmt">Select Time</span><span>:</span>
<select id="first" name="first" class="tx_bx" value="">
<option value="">- Select -</option>
<option value="">#1 only: 1pm</option>
<option value="">#1 only: 1:30pm</option>
<option value="">#1 only: 2pm</option>
<option value="">#1 only: 2:30pm</option>
<option value="">#1 only: 3:30pm</option>
<option value="">#1 only: 4pm</option>
<option value="">#1 only: 4:30 pm</option>
<option value="">#1 only: 5:00pm</option>
<option value="">9am</option>
<option value="">9:30am</option>
<option value="">10 am</option>
<option value="">10:30am</option>
<option value="">11 am</option>
<option value="">11:30am</option>
<option value="">12:30 pm</option>
<option value="">1:00pm</option><option value="">1:30pm</option>
</select>
</div>
<div class="sgl_part_div">
<span class="cmt">Select Session</span><span>:</span>
<select id="second" name="second" class="tx_bx" value="">
<option value="">- Select -</option>
<option value="">Session #1: Tues May 31st - Fri June 10th (1-5:30PM)</option>
<option value="">Session #2: Tues June 14th - Fri June 24th (9-2:00PM)</option>
<option value="">Session #3: Tues June 28th - Fri July 8th (9-2:00PM)</option>
<option value="">Session #4: Tues July 12th - Fri July 22nd (9-2:00PM)</option>
<option value="">Session #5: Tues July 26th - Fri Aug 5th (9-2:00PM)</option>
<option value="">Session #6: Tues Aug 9th - Fri Aug 19th (9-2:00PM)</option>
</select>
</div>
<div class="sgl_part_div">
<span class="cmt">Select Time</span><span>:</span>
<select id="second" name="second" class="tx_bx" value="">
<option value="">- Select -</option>
<option value="">#1 only: 1pm</option>
<option value="">#1 only: 1:30pm</option>
<option value="">#1 only: 2pm</option>
<option value="">#1 only: 2:30pm</option>
<option value="">#1 only: 3:30pm</option>
<option value="">#1 only: 4pm</option>
<option value="">#1 only: 4:30 pm</option>
<option value="">#1 only: 5:00pm</option>
<option value="">9am</option>
<option value="">9:30am</option>
<option value="">10 am</option>
<option value="">10:30am</option>
<option value="">11 am</option>
<option value="">11:30am</option>
<option value="">12:30 pm</option>
<option value="">1:00pm</option><option value="">1:30pm</option>
</select>
</div>
<div class="sgl_part_div">
<span class="cmt">Select Session</span><span>:</span>
<select id="third" name="third" class="tx_bx" value="">
<option value="">- Select -</option>
<option value="">Session #1: Tues May 31st - Fri June 10th (1-5:30PM)</option>
<option value="">Session #2: Tues June 14th - Fri June 24th (9-2:00PM)</option>
<option value="">Session #3: Tues June 28th - Fri July 8th (9-2:00PM)</option>
<option value="">Session #4: Tues July 12th - Fri July 22nd (9-2:00PM)</option>
<option value="">Session #5: Tues July 26th - Fri Aug 5th (9-2:00PM)</option>
<option value="">Session #6: Tues Aug 9th - Fri Aug 19th (9-2:00PM)</option>
</select>
</div>
<div class="sgl_part_div">
<span class="cmt">Select Time</span><span>:</span>
<select id="third" name="third" class="tx_bx" value="">
<option value="">- Select -</option>
<option value="">#1 only: 1pm</option>
<option value="">#1 only: 1:30pm</option>
<option value="">#1 only: 2pm</option>
<option value="">#1 only: 2:30pm</option>
<option value="">#1 only: 3:30pm</option>
<option value="">#1 only: 4pm</option>
<option value="">#1 only: 4:30 pm</option>
<option value="">#1 only: 5:00pm</option>
<option value="">9am</option>
<option value="">9:30am</option>
<option value="">10 am</option>
<option value="">10:30am</option>
<option value="">11 am</option>
<option value="">11:30am</option>
<option value="">12:30 pm</option>
<option value="">1:00pm</option><option value="">1:30pm</option>
</select>
</div>
</div>