It is stipulated that uploaded files can only be pictures. If they are other files, they cannot be uploaded. What is this restriction?
<code>if($_SERVER['REQUEST_METHOD']=='POST'){
if(is_uploaded_file($_FILES['up']['tmp_name'])){
$path='./upload/';
is_dir($path) || mkdir($path,0777,true);
$type=ltrim(strchr($_FILES['up']['type'],'/'),'/');
$fileName = time().mt_rand(0, 9999).'.'.$type;
$fullpath = $path . $fileName;
move_uploaded_file($_FILES['up']['tmp_name'], $fullpath);
}
}</code>It is stipulated that uploaded files can only be pictures. If they are other files, they cannot be uploaded. What is this restriction?
<code>if($_SERVER['REQUEST_METHOD']=='POST'){
if(is_uploaded_file($_FILES['up']['tmp_name'])){
$path='./upload/';
is_dir($path) || mkdir($path,0777,true);
$type=ltrim(strchr($_FILES['up']['type'],'/'),'/');
$fileName = time().mt_rand(0, 9999).'.'.$type;
$fullpath = $path . $fileName;
move_uploaded_file($_FILES['up']['tmp_name'], $fullpath);
}
}</code>
<code><?php
//可以上传的类型
$arr_file_type = ['image/gif'];
//如果上传的类型 不在配置的类型数组里面
if(!in_array($_FILES['fileName']['type'],$arr_file_type))
{
$msg ='文件类型有误！';
return false;
}
</code>
Judging by the extension, there are risks
Judge by MIME Types
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