PHP LongBlob上传/下载不支持图片

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接是否成功
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 获取上传的图片文件
$image = $_FILES['image']['tmp_name'];

// 将图片文件读取为二进制数据
$imageData = file_get_contents($image);

// 准备SQL语句
$sql = "INSERT INTO images (image_data) VALUES (?)";

// 创建预处理语句
$stmt = $conn->prepare($sql);

// 绑定参数
$stmt->bind_param("b", $imageData);

// 执行预处理语句
if ($stmt->execute()) {
    echo "图片上传成功";
} else {
    echo "图片上传失败";
}

// 关闭连接
$stmt->close();
$conn->close();
?>

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接是否成功
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 查询图片数据
$sql = "SELECT image_data FROM images WHERE id = ?";

// 创建预处理语句
$stmt = $conn->prepare($sql);

// 绑定参数
$id = 1; // 图片的ID
$stmt->bind_param("i", $id);

// 执行预处理语句
$stmt->execute();

// 获取查询结果
$stmt->bind_result($imageData);
$stmt->fetch();

// 输出图片数据
header("Content-type: image/jpeg");
echo $imageData;

// 关闭连接
$stmt->close();
$conn->close();
?>