PHP submit multiple forms with 1 button

Question

I want to submit multiple forms with only 1 buttons outside all of the form. This is the index.php

 <form id="allform" class = "NameInput" action="addToCartFood.php" method="POST">
            Name:   <input type="text" class = "inputName" name="Name" value=""><br>
 </form>

 <form id="allform" action="addToCartFood.php"  method="POST">
            Date:       
            <select name="Date" class = "Date">
                <option value="26">26</option>
                <option value="27">27</option>
                <option value="28">28</option>
            </select>
            July 2020
</form>
<form id="allform" action="addToCartFood.php" method="POST">
            Adult:      
            <select id = "selectboxAdult" name="Adult" class = "Adult" onchange = "calculateAll(<?php echo $_SESSION['price'];?>)">
                <option value="1">1</option>
                <option value="2">2</option>
                <option value="3">3</option>
                <option value="4">4</option>
            </select>
</form>

<input  type="submit" class = "submitbtn" form="allform" value="Add to Cart">

And when i click the button, it will go to the addToCartFood.php and these are the codes

$_SESSION['Date'] = $_POST['Date'];
$_SESSION['Name'] = $_POST['Name'];
$_SESSION['AdultQ'] = $_POST['Adult'];
$_SESSION['KidsQ'] = $_POST['Kids'];
$_SESSION['telnum'] = $_POST['telnum'];
$_SESSION['comment'] = $_POST['comment'];

Thank you in advance

Answer 1

why multiple forms ? just merge them all in one form only as action and method is same for all

<form id="allform" class = "NameInput" action="addToCartFood.php" method="POST">
            Name:   <input type="text" class = "inputName" name="Name" value=""><br>
            Date:       
            <select name="Date" class = "Date">
                <option value="26">26</option>
                <option value="27">27</option>
                <option value="28">28</option>
            </select>
            July 2020
            Adult:      
            <select id = "selectboxAdult" name="Adult" class = "Adult" onchange = "calculateAll(<?php echo $_SESSION['price'];?>)">
                <option value="1">1</option>
                <option value="2">2</option>
                <option value="3">3</option>
                <option value="4">4</option>
            </select>

<input  type="submit" class = "submitbtn" form="allform" value="Add to Cart">

</form>