How to change the file type PHP file type detection code

$filename = "D:\296.mid";
$file = fopen($filename, "rb");
$bin = fread($file, 2); //Read only 2 bytes
fclose($file);
$strInfo = @unpack("c2chars", $bin);
$typeCode = intval($strInfo['chars1'].$strInfo['chars2']);
$fileType = ' ';
switch ($typeCode)
{
case 7790:
$fileType = 'exe';
break;
case 7784:
$fileType = 'midi';
break;
case 8297:
$fileType = 'rar ';
break;
case 255216:
$fileType = 'jpg';
break;
case 7173:
$fileType = 'gif';
case 13780:
$fileType = 'png';
break;
default:
echo 'unknown';
}
echo 'this is a(an) '.$fileType.' file:'.$typeCode;
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The above introduces how to change the file type PHP file type judgment code, including how to change the file type. I hope it will be helpful to friends who are interested in PHP tutorials.