PHP is_file determines whether the given file name is a normal file

The is_file() function checks to see if the specified file name is a normal file.
Is_file - Tells whether the filename is a regular file
usage

Bool is_file (string $filename) $file is a required parameter
Returns TRUE if the file exists and is a normal file.

Consider a classic example of a test is_file

 
<?php 
var_dump(is_file('a_file.txt')) . "n"; 
var_dump(is_file('/usr/bin/')) . "n"; 
?> 

The above example will output:
Bool (true)
Bool (false)
Use two

 
<?php 
function isfile($file){ 
return preg_match('/^[^.^:^?^-][^:^?]*.(?i)' . getexts() . '$/',$file); 
//first character cannot be . : ? - subsequent characters can't be a : ? 
//then a . character and must end with one of your extentions 
//getexts() can be replaced with your extentions pattern 
} 
function getexts(){ 
//list acceptable file extensions here 
return '(app|avi|doc|docx|exe|ico|mid|midi|mov|mp3| 
mpg|mpeg|pdf|psd|qt|ra|ram|rm|rtf|txt|wav|word|xls)'; 
} 
echo isfile('/Users/YourUserName/Sites/index.html'); 
?> 

Examples of three

 
<?php 
function deletefolder($path) 
{ 
if ($handle=opendir($path)) 
{ 
while (false!==($file=readdir($handle))) 
{ 
if ($file<>"." AND $file<>"..") 
{ 
if (is_file($path.'/'.$file)) 
{ 
@unlink($path.'/'.$file); 
} 
if (is_dir($path.'/'.$file)) 
{ 
deletefolder($path.'/'.$file); 
@rmdir($path.'/'.$file); 
} 
} 
} 
} 
} 
?> 

This function deletes everything defined by the folder