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

The is_file() function checks whether 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.
Let’s take a look at a classic example of testing is_file

Copy the code The code is as follows:

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

The above example will output:
bool(true)
bool(false)
Usage 2

Copy the code The code is as follows:

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');
?>

Example 3

Copy code The code is as follows:

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 all things in the defined folder

The above has introduced how php is_file determines whether a given file name is a normal file, including aspects of it. I hope it will be helpful to friends who are interested in PHP tutorials.