Question

我有一个代码，可以像这样在会话中添加一个数组：

array_push($_SESSION['cart']['1'] = 3);
array_push($_SESSION['cart']['18'] = 1);

这会添加项目ID＆＃34; 1＆＃34;数量＆＃34; 3＆＃34;并添加项目ID＆＃34; 18＆＃34;数量＆＃34; 1＆＃34;。我想在购物车页面上显示数据库中的这些项目。我在php或sql中表现不佳，但有点像：

while (list ($id, $quantity) = each ($_SESSION['cart'])) { 
$results = $conn->query("SELECT * FROM products ORDER BY id ASC");
}

并执行类似查找$id(from session) = $id(from database)的操作，以便将会话显示为来自数据库的信息。使用项目名称，项目描述，项目价格和数量。

Answer 1

以下是一个快速示例，重点介绍了您尝试从$ _SESSION中检索的内容（id_item）：

http://www.tehplayground.com/#Iyf7c0LTM

$arr = array();
$arr['cart']['1'] = 3;
$arr['cart']['18'] = 5;

// This loop will display every id_item that had be added to the "cart"
foreach($arr['cart'] as $row)
{
    print "id_item : " . $row . "\n";
}

你现在可以使用你的sql查询：

$sql = "SELECT * FROM products WHERE id =". $row;

编辑 - 由于您不清楚，我直接回答了问题：

<?php
session_start();

// Examples of shopped items (added to $_SESSION['cart'])
$_SESSION['cart']['1'] = 3;
$_SESSION['cart']['18'] = 5;

// This loop will display every id_item that had be added to the "cart"
// Further informations how foreach works with array 
// https://stackoverflow.com/questions/10057671/how-foreach-actually-works
foreach($_SESSION['cart'] as $row)
{
    print "id_item : " . $row . "\n";
}

// Full Display to help understanding the process
print "<pre>";
print_r($_SESSION['cart']);
print "</pre>";

?>

关于＆＃34; foreach如何与数组交互的高级解释＆＃34; ：here

编辑2： 填充数据库变量+表的列名

<?php

$servername = "localhost";
$username = "root";
$password = "";
$dbname = "";

$mysqli = new mysqli($servername, $username, $password, $dbname);

// check connection
if ($mysqli->connect_errno) {
    printf("Connect failed: %s\n", $mysqli->connect_error);
    exit();
}

// Query the DB - Get itemID & quantity added in the cart table
$query = "SELECT itemID, itemQuantity FROM cart";
$result = $mysqli->query($query);

// Return the result into an array
$res_array = $result->fetch_array();

// Add the items into $_SESSION
// Pattern : $_SESSION['cart']['$itemId'] = $itemQuantity

foreach($res_array as $row)
    $_SESSION['cart'][($row['itemID'])] = $row['itemQuantity']

print "<pre>";
print_r($_SESSION['cart']);
print "</pre>";
?>

示例：here

Answer 2

不是从数据库中获取所有内容，然后在php中进行比较，您可以执行类似的操作，只获取所需的记录：

"SELECT * FROM products WHERE id IN(1,18) ORDER BY id ASC"

PHP可能就像：$in = implode(",", $_SESSION['cart']);一样简单，尽管你也应该确保防止SQL注入。

如何从会话数组中选择数据库中的项目？

2 个答案: