php 多条件筛选功能

<?php
// 假设我们有一个数据库连接
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

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

if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 获取用户输入的筛选条件
$min_price = $_GET['min_price'] ?? '';
$max_price = $_GET['max_price'] ?? '';
$category = $_GET['category'] ?? '';

// 构建 SQL 查询语句
$sql = "SELECT * FROM products WHERE 1=1";
$params = [];

if (!empty($min_price)) {
    $sql .= " AND price >= ?";
    $params[] = $min_price;
}

if (!empty($max_price)) {
    $sql .= " AND price <= ?";
    $params[] = $max_price;
}

if (!empty($category)) {
    $sql .= " AND category = ?";
    $params[] = $category;
}

// 执行查询
$stmt = $conn->prepare($sql);
$stmt->bind_param(str_repeat("s", count($params)), ...$params);
$stmt->execute();
$result = $stmt->get_result();

// 处理结果
while ($row = $result->fetch_assoc()) {
    echo "ID: " . $row["id"]. " - Name: " . $row["name"]. " - Price: " . $row["price"]. " - Category: " . $row["category"]. "<br>";
}

$stmt->close();
$conn->close();
?>