User defined button in PHP

Question

So I am trying to make a shopping cart. What I need to do is send a product id and a quantity the user wants to buy to another file cart.php.

Here is a section of my code:

for($i=0;$i<$numOfRows;$i++){
  $prodID=mysql_result($result, $i, "ProductID");
  $prodTitle=mysql_result($result, $i, "Title");
  $prodAuthor=mysql_result($result, $i, "Author1");
  $prodPrice=mysql_result($result, $i, "Price");

  Print"<h4>ID: $prodID \n     </h4>";
  Print"<h4>Title: $prodTitle \n       </h4>";
  Print"<h4>Author: $prodAuthor \n     </h4>";
  Print"<h4>Price: $ $prodPrice \n     </h4>";

  Print" <form method ='POST'>";
  Print"<p><label> Quantity";
  Print"<input name='quantity' type='text' pattern='[1-9]{1,50}'/>";
  Print"</label>";
  Print"<input type='button' value='Add To Cart' onClick='cart.php?pid=$prodID'/>";
  Print"</p></form>";
}

If I get rid of the form and just have <a href='cart.php?pid=$prodID'>Add To Cart</a> it sends the id but I also need the quantity to go along with it. Whenever I click Add To Cart it doesn’t send me to my cart.php.

score 1 · Answer 1 · edited May 23 '17 at 12:22

If you want use the POST method add a hidden input with the pid info. See the example:

print" <form method ='POST' action ='cart.php'>";
print"<p><label> Quantity";
print"<input name='quantity' type='text' pattern='[1-9]{1,50}'/>";
print"</label>";
print"<input type='hidden' name = 'pid' value='$prodID'>";
print"<input type='button' value='Add To Cart'/>";
print"</p></form>";

If you want use the GET method see the @Ghost answer

dbinns66 · Answer 2 · 2015-05-02T02:24:47.507

Your onlick is doing a method GET while your form indicates a method POST and you're not specifying "action='cart.php'" in your form tag... there may be other issue but...

try this

for($i=0;$i<$numOfRows;$i++)
{
   $prodID=mysql_result($result, $i, "ProductID");
   $prodTitle=mysql_result($result, $i, "Title");
   $prodAuthor=mysql_result($result, $i, "Author1");
   $prodPrice=mysql_result($result, $i, "Price");

   Print"<h4>ID: $prodID \n    </h4>";
   Print"<h4>Title: $prodTitle \n      </h4>";
   Print"<h4>Author: $prodAuthor \n    </h4>";
   Print"<h4>Price: $ $prodPrice \n    </h4>";

   Print"<form action='cart.php' method ='POST'>";
   Print"<p><label> Quantity";
   Print"<input name='pid' type = 'hidden' value='$prodID'>";
   Print"<input name='quantity' type='text' pattern='[1-9]{1,50}'/>";
   Print"</label>";
   Print"<input type='submit' value='Add To Cart'>";
   Print"</p></form>";
}

score 0 · Accepted Answer · edited May 23 '17 at 11:50

Why not just let it submit the form normally. And use a normal type="submit" with method="GET":

echo "<form method ='GET' action='cart.php'>";
    echo "<p><label> Quantity: ";
        echo "<input name='quantity' type='text' pattern='[1-9]{1,50}'/>";
    echo "</label>";
    echo "
        <input type='hidden' name='pid' value='$prodID' />
        <input type='submit' value='Add To Cart' />
    ";
echo "</p></form>";

Of course in cart.php, just use $_GET all through out:

<?php

if(!empty($_GET['quantity']) && !empty($_GET['pid'])) {
    $quantity = $_GET['quantity'];
    $pid = $_GET['pid'];
    // do the rest of codes below
}

Obligatory Note:

Please, don't use mysql_* functions in new code. They are no longer maintained and are officially deprecated. See the red box? Learn about prepared statements instead, and use PDO or MySQLi - this article will help you decide which. If you choose PDO, here is a good tutorial.

User defined button in PHP

3 Answers3