finfo_file()

finfo::file

(PHP >= 5.3.0, PECL fileinfo >= 0.1.0)

返回一个文件的信息

说明

过程化风格
finfo_file(resource $finfo,string $file_name= NULL[,int $options= FILEINFO_NONE[,resource $context= NULL]]): string面向对象风格
publicfinfo::file(string $file_name= NULL[,int $options= FILEINFO_NONE[,resource $context= NULL]]): string

本函数用来获取一个文件的信息。

参数

$finfo

finfo_open()函数所返回的 fileinfo 资源。

$file_name

要检查的文件名。

$options

一个Fileinfo 常量或多个Fileinfo 常量进行逻辑或运算。

$context

关于contexts的更多描述，请参考Stream 函数。

返回值

返回$file_name参数指定的文件信息。发生错误时返回FALSE。

范例

finfo_file()例程

以上例程的输出类似于：

text/html
image/gif
application/vnd.ms-excel

参见

• finfo_buffer()别名 finfo_buffer()

Tempting as it may seem to use finfo_file() to validate uploaded image files (Check whether a supposed imagefile really contains an image), the results cannot be trusted. It's not that hard to wrap harmful executable code in a file identified as a GIF for instance.
A better & safer option is to check the result of:
if (!$img = @imagecreatefromgif($uploadedfilename)) {
 trigger_error('Not a GIF image!',E_USER_WARNING);
 // do necessary stuff
}

The way HOWTO get MIME-type of remote file. 

Just noting (because I ran into it!) that the current implementation of finfo_file has a known bug which causes PHP to allocate huge amounts of memory when certain strings are present in text files that it is examining.
See https://bugs.php.net/bug.php?id=69224 for more info.

Well, i have a great probleam with that, MS Office 2007 extensions (pptx, xlsx, docx) do not have a default Mime type, they have "application/zip" mime type, so, to fix that, i do one little function to verify the extension.
That function allow's you to be safe of fake extensions hack. 

I was getting application/octet-stream or "