<?php
$carName = $_POST['carName'];
$carDesc = $_POST['carDesc'];
/*使用$_FILES方法获取到图片相关的二维数组$_FILES['carPic'] 
 Array ( [name] => x1.jpeg [type] => image/jpeg [tmp_name] => C:\Windows\php79E.tmp [error] => 0 [size] => 8967 ) 错误中有超过文件大小限制，
 在百度搜索可以 解决 php.ini在小皮的设置里可以找到*/
$carPic = $_FILES['carPic'];
//print_r($carPic);
//第一步：判断图片上传是否有误
if($carPic['error']){
    echo "<script>alert('图片上传错误');history.back();</script>";
    exit;
}
//第二步：判断文件格式大小是否正确
//先判断文件大小是否大于2MB size给的是字节
if($carPic['size'] > 2*1024*1024 ) {
    echo "<script>alert('图片大小不能超过2MB');history.back();</script>";
    exit;
}
//判断文件类型是否正确
//使用$_FILES中的type
$allowType = array('image/gif','image/jpeg','image/jpg','image/pjpeg','image/png');
if(!in_array($carPic['type'],$allowType)){
    //说明不存在指定类型
    echo "<script>alert('图片类型错误，只能是jpg、png、gif图片。');history.back();</script>";
    exit;
}
//使用$_FILES中的name判断
$allowExt = array('gif','jpeg','jpg','pjpeg','png');
$nameArray = explode('.',$carPic['name']);
$nameExt = strtolower(end($nameArray));
if(!in_array($nameExt,$allowExt)){
    //说明不存在指定类型
    echo "<script>alert('图片类型错误，只能是jpg、png、gif图片。');history.back();</script>";
    exit;
}
//采用uniqid函数生成唯一不重复的名称并且和拓展名链接
$fileName = uniqid().".".$nameExt;
//将缓存区图片移动到指定的文件夹 
$result = move_uploaded_file($carPic['tmp_name'],"img/".$fileName);
if(!$result){
    //上传不成功
    echo "<script>alert('图片保存失败');history.back();</script>";
    exit;
}
//第三步 写入数据库
include_once 'conn.php';
$sql = "INSERT INTO carinfo (carName,carDesc,carPic) values ('$carName','$carDesc','$fileName')";
$result = mysqli_query($conn,$sql);
if($result){
    echo "<script>alert('车辆添加成功');location.href='admin.php';</script>";
} else {
    echo "<script>alert('车辆添加失败');history.back();</script>";
} 
?>