php get upload file type get file suffix

php tutorial Get upload file type Get file suffix This tutorial provides three ways to get upload files and image types, the method is very simple The first two types is defined first, and then in_array judgment, the last step is to use fopen read the first two bytes, determine.
* /

// Get the image format, including jpg, png, gif
function get_type ($ img_name) // Get the image file type
{
if (preg_match ("/. (jpg | jpeg | gif | png | bmp) $ / i", $ img_name, $ matches)) {
$ type = strtolower ($ matches [1]);
} else {
$ type = "string";
}
return $ type;
}

/ / Determine the type of file upload
$ allowedextensions = array ("txt", "csv", "htm", "html", "xml",
"css tutorial", "doc", "xls", "rtf", "ppt", "pdf", "swf", "flv", "avi"
"wmv", "mov", "jpg", "jpeg", "gif", "png");
foreach ($ _files as $ file) {
if ($ file ['tmp_name']> '') {
if (! in_array (end (explode (".",
strtolower ($ file ['name']))),
$ allowedextensions)) {
die ($ file ['name']. 'is an invalid file type!'
'<a href="#############
'& lt; & lt go back back </a>');
}
}
}

// Another kind of reading file and image type

function checktitle ($ filename) {
$ 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';
break;
case 6677:
$ filetype = 'bmp';
break;
case 13780:
$ filetype = 'png';
break;
default:
$ filetype = 'unknown'. $ typecode;
}
// fix
if ($ strinfo ['chars1'] == '- 1' && $ strinfo ['chars2'] == '- 40') {
return 'jpg';
}
if ($ strinfo ['chars1'] == '- 119' && $ strinfo ['chars2'] == '80') {
return 'png';
}
return $ filetype;
}

?>