10 little known functions in PHP

PHP has a rich set of built-in functions, many of which we've used before, but there are many that most of us are not familiar with that are extremely useful. In this article, I've listed some little-known PHP functions that will brighten your eyes.

levenshtein()

Have you ever needed to know how different two words are? This function is here to help you. It can compare the degrees of two strings.

Usage:

 
<?php 
$str1 = "carrot"; 
$str2 = "carrrott"; 
echo levenshtein($str1, $str2); //Outputs 2 
?> 

get_defined_vars()

This is a useful function to use when debugging debug. This function returns a multidimensional array containing all the defined variables.

Usage:

<?php
print_r(get_defined_vars());
?>

php_check_syntax()

This function is very useful for checking the syntax of PHP. For technical reasons, this function has been removed as of PHP 5.05.

Usage:

 
<?php 
$error_message = ""; 
$filename = "./php_script.php"; 
if(!php_check_syntax($filename, &$error_message)) { 
echo "Errors were found in the file $filename: $error_message"; 
} else { 
echo "The file $filename contained no syntax errors"; 
} 
?>

ignore_user_abort()

This function is used to reject requests from browser-side users to terminate the script execution. Normally the client exits and the server-side script stops running.

Usage:

<?php
ignore_user_abort();
?>

highlight_string()

The highlight_string() function is useful when you want to display PHP code on a page. This function highlights the PHP code you provide using the built-in PHP syntax to highlight the defined color. This function takes two arguments. The first argument is a string, indicating that the string needs to be highlighted. The second parameter, if set to TRUE, returns the highlighted code as the return value.

Usage:

<?php
highlight_string('<?php phpinfo(); ?>');
?>

highlight_file

PHP - This is a very useful PHP function that returns the specified PHP file and highlights the contents of the file syntactic. The highlighted code is handled with HTML tags.

Usage:

<?php
highlight_file("php_script.php");
?>

php_strip_whitespace

This function is similar to the previous show_source() function, but it removes comments and Spaces in the file.

Usage:

<?php
echo php_strip_whitespace("php_script.php");
?>

ge
owser

This function reads the browscap.ini file and returns browser compatibility information.

Usage:

<?php
echo $_SERVER['HTTP_USER_AGENT'];
$browser = get_browser();
print_r($browser);
?>

memory_get_usage(),memory_ge

ak_usage(),getrusage()

memory_get_usage() returns memory usage, memory_ge

ak_usage() returns peak memory usage, and getrusage() returns CUP usage. These functions can give you some useful information when debugging PHP code performance. Note, however, that one of these functions is invalid on Window.

Usage:

 
<?php 
echo "Initial: ".memory_get_usage()." bytes \n"; 
echo "Peak: ".memory_get_peak_usage()." bytes \n"; 
$data = getrusage(); 
echo "User time: ". 
($data['ru_utime.tv_sec'] + 
$data['ru_utime.tv_usec'] / 1000000); 
echo "System time: ". 
($data['ru_stime.tv_sec'] + 
$data['ru_stime.tv_usec'] / 1000000); 
?>

gzcompress(), gzuncompress()

These functions are used to compress and decompress string data. Their compressibility can reach about 50%. The other functions gzencode() and gzdecode() achieve similar results, but use different compression algorithms.

Usage:

 
<?php 
$string = 
"Lorem ipsum dolor sit amet, consectetur 
adipiscing elit. Nunc ut elit id mi ultricies 
adipiscing. Nulla facilisi. Praesent pulvinar, 
sapien vel feugiat vestibulum, nulla dui pretium orci, 
non ultricies elit lacus quis ante. Lorem ipsum dolor 
sit amet, consectetur adipiscing elit. Aliquam 
pretium ullamcorper urna quis iaculis. Etiam ac massa 
sed turpis tempor luctus. Curabitur sed nibh eu elit 
mollis congue. Praesent ipsum diam, consectetur vitae 
ornare a, aliquam a nunc. In id magna pellentesque 
tellus posuere adipiscing. Sed non mi metus, at lacinia 
augue. Sed magna nisi, ornare in mollis in, mollis 
sed nunc. Etiam at justo in leo congue mollis. 
Nullam in neque eget metus hendrerit scelerisque 
eu non enim. Ut malesuada lacus eu nulla bibendum 
id euismod urna sodales. "; 
$compressed = gzcompress($string); 
$original = gzuncompress($compressed); 
?> 

Can you think of any other functions that might be useful? Please share in the comments!