我正在做一個添加到購物車程序。我列出幾個產品在一個page.but我只能改變數量的第一個產品

Question

我是新來的PHP。我正在做一個添加到購物車program.i列出幾個產品在一個頁面上，但我只能更改列表中的第一個產品的數量。而其他的則採用默認值1.

該程序用於在單個頁面上列出多個產品，從數據庫中檢索。有不同的類別，因此我從URL中獲取cat_id。

custproduct.php 

<?php 
session_start(); 
if (isset($_GET['id'])) 
{ 
    // echo"id: ".$_GET['id']; 
include ('custdb1.php'); 
echo "<h2>List of Products:</h2>"; 
$sql = "SELECT * FROM `product` WHERE `cat_id`=".$_GET['id']; 
$result = $conn->query($sql); 
if ($result->num_rows > 0) { 
    // output data of each row 
    while($row = $result->fetch_assoc()) { 
echo "<br> Product ID: ". $row["pro_id"]. " - Product Name: ". $row["pro_name"]. "<br>"; 
echo "<img src='upload/".$row['pro_img']."'/>"; 
echo "<br> Price: Rs. ". $row["pro_price"]. " "; 
echo "<br>"; 
echo "Quantity: <input type='text' name='qty' id='qty' value='1'>"; 
echo "<br>"; 
echo "<button onclick='addtocart(".$row['pro_id'].")'>Add To Cart</button>" ; 
} 

} 
} 
else { 
    echo "0 results"; 
} 

?> 

<script> 

function addtocart(id) 
{ 

var qty = document.getElementById('qty').value; 
document.write("qty"); 
window.location ="cart.php?id="+id+"&qty="+qty; 

} 

</script> 

這cart.php page.this頁面用於增加產品在cart.the客戶點擊下方「查看列表」

<?php 

session_start(); 

include('custdb1.php'); 
//$id = isset($_GET['id']) ? $_GET['id'] : ''; 
if (isset($_GET['id'])) 
{ 
    $id=$_REQUEST["id"]; 
    $qty=$_REQUEST["qty"]; 
//echo"qty=".$qty; 

$_SESSION['cart'][$id] = array('id'=> $id,'qty'=> $qty); 

$sql = "SELECT `pro_img` FROM `product` WHERE `pro_id`=".$id; 
$result = $conn->query($sql); 

if ($result->num_rows > 0) { 
    while($row = $result->fetch_assoc()) { 
     echo "quantity:".$qty.'<br>'; 
echo "id:".$id.'<br>'; 
echo "<img src='upload/".$row['pro_img']."'/>"; 

    } 
} 
} 
echo "<h4 align='center'> click here to <a href='shoppingcart.php'>see list</a> </h4>"; 
echo "<h4 align='center'> click here to <a href='custprofile.php'>Continue Shopping</a> </h4>"; 
?> 

這是鏈接看到他的車購物cart.php.this頁面顯示購物車中添加的產品...即客戶可以看到他的購物車。

<?php 

session_start(); 
include('custdb1.php'); 
echo "<pre>"; 

$value=$_SESSION['cart']; 
//print_r($value); 
foreach ($value as $key=> $final_val){ 

       $cat_id = $key; 
       $pro_id = $final_val['id']; 
       $qty = $final_val['qty']; 
      echo"product id:".$pro_id; 
      echo"quantity:".$qty; 
       $sql = "SELECT * FROM `product` WHERE `pro_id`=".$pro_id; 

$result = $conn->query($sql); 

if ($result->num_rows > 0) { 
    // output data of each row 
    while($row = $result->fetch_assoc()) { 
     echo "<br> Product ID: ". $row["pro_id"]. " - Product Name: ". $row["pro_name"]. "<br>"; 
     echo "<img src='upload/".$row['pro_img']."'/>"; 
     // echo "<button onclick='update(".$row['pro_id'].")'>update</button>" ; 
     // echo "<h4 align='left'><a href='update.php'>update cart</a> </h4>"; 
} 

} 
else { 
    echo "0 results"; 
} 
} 

echo "<h4 align='center'> click here to <a href='custprofile.php'>Continue Shopping</a> </h4>"; 
?> 

Answer 1

設置數量HTML的id與產品ID

while($row = $result->fetch_assoc()) { 
echo "<br> Product ID: ". $row["pro_id"]. " - Product Name: ". $row["pro_name"]. "<br>"; 
echo "<img src='upload/".$row['pro_img']."'/>"; 
echo "<br> Price: Rs. ". $row["pro_price"]. " "; 
echo "<br>"; 
echo "Quantity: <input type='text' name='qty' id='". $row["pro_id"]. "' value='1'>"; 
echo "<br>"; 
echo "<button onclick='addtocart(".$row['pro_id'].")'>Add To Cart</button>" ; 

}

然後可以選擇與相應的產品ID設置爲它的id輸入元件

function addtocart(id) 
{ 

var qty = document.getElementById(id).value; 
document.write("qty"); 
window.location ="cart.php?id="+id+"&qty="+qty; 

}