PHP商城功能教程：创建库存和库存管理系统

<?php
// 连接数据库 
$conn = mysqli_connect("localhost", "root", "", "inventory_management");

// 查询所有商品和库存信息
$query = "SELECT p.name, p.price, p.description, s.quantity FROM products p INNER JOIN stock s ON p.id = s.product_id";
$result = mysqli_query($conn, $query);

// 显示商品和库存信息
echo "<h1>库存管理系统</h1>";
echo "<table>";
echo "<tr><th>商品名称</th><th>价格</th><th>描述</th><th>库存数量</th></tr>";
while($row = mysqli_fetch_assoc($result)) {
    echo "<tr><td>".$row['name']."</td><td>".$row['price']."</td><td>".$row['description']."</td><td>".$row['quantity']."</td></tr>";
}
echo "</table>";

// 关闭数据库连接
mysqli_close($conn);
?>

<?php
if($_SERVER["REQUEST_METHOD"] == "POST") {
    // 获取用户输入的商品信息
    $name = $_POST["name"];
    $price = $_POST["price"];
    $description = $_POST["description"];

    // 连接数据库
    $conn = mysqli_connect("localhost", "root", "", "inventory_management");

    // 添加商品到products表
    $query = "INSERT INTO products (name, price, description) VALUES ('$name', '$price', '$description')";
    mysqli_query($conn, $query);

    // 获取新增商品的id
    $product_id = mysqli_insert_id($conn);

    // 添加库存信息到stock表
    $quantity = $_POST["quantity"];
    $query = "INSERT INTO stock (product_id, quantity) VALUES ($product_id, $quantity)";
    mysqli_query($conn, $query);

    // 提示用户商品添加成功
    echo "商品已成功添加！";

    // 关闭数据库连接
    mysqli_close($conn);
}
?>

<form method="post" action="">
    <label for="name">商品名称:</label>
    <input type="text" name="name" required><br><br>
    <label for="price">价格:</label>
    <input type="number" name="price" min="0" step="0.01" required><br><br>
    <label for="description">描述:</label><br>
    <textarea name="description" rows="4" cols="50" required></textarea><br><br>
    <label for="quantity">库存数量:</label>
    <input type="number" name="quantity" min="0" required><br><br>
    <input type="submit" value="添加商品">
</form>

<?php
if($_SERVER["REQUEST_METHOD"] == "POST") {
    // 获取用户输入的商品id和库存数量
    $product_id = $_POST["product_id"];
    $quantity = $_POST["quantity"];

    // 连接数据库
    $conn = mysqli_connect("localhost", "root", "", "inventory_management");

    // 更新stock表中的库存数量
    $query = "UPDATE stock SET quantity=$quantity WHERE product_id=$product_id";
    mysqli_query($conn, $query);

    // 提示用户库存数量已更新
    echo "库存数量已成功更新！";

    // 关闭数据库连接
    mysqli_close($conn);
}
?>

<form method="post" action="">
    <label for="product_id">请选择商品:</label>
    <select name="product_id">
        <?php
        // 连接数据库
        $conn = mysqli_connect("localhost", "root", "", "inventory_management");

        // 查询所有商品
        $query = "SELECT * FROM products";
        $result = mysqli_query($conn, $query);

        // 显示商品选项
        while($row = mysqli_fetch_assoc($result)) {
            echo "<option value=".$row['id'].">".$row['name']."</option>";
        }

        // 关闭数据库连接
        mysqli_close($conn);
        ?>
    </select><br><br>
    <label for="quantity">库存数量:</label>
    <input type="number" name="quantity" min="0" required><br><br>
    <input type="submit" value="更新库存数量">
</form>