Some Handy php string function

Published on : April 27, 2026

Author: wahid

Category: Uncategorized

str_split()

str_split() works like explode() in some manner, it is used for splitting a string into an array.

Syntax:

str_split($mystring, length);

Example:

<?php
print_r(str_split("What"));
?>

 
Output:

Array
(
[0] => W
[1] => h
[2] => a
[3] => T
)

str_replace()

If you want to replace some specified characters with other characters in PHP, str_replace() is the best choice. It has many rules like:

If we want to search a string in an array, it returns as an array.
Find and Replace is performed with each array element as we want to search a string in an array.
If we are finding an array and also replacing with it with an array, an empty string will be used as replace.
In case, replace is a string and find is an array, then it uses replace sting as find value.

Syntax:
str_replace(find, replace, string, count);

Example:
<?php
echo str_replace("How", "Dear", "How Di");
?>

Output:

How Dear

md5()

md5() function calculates Message-Digest Algorithm (md5) hash of a string. It has two parameters, first one is required and second one is optional which was included in PHP 5.0.

Syntax:

md5($str, raw);

Example:

<?php
$mystr = "How Are You";
echo md5($mystr);
?>

Output:

9e227bb366c119c7f27a7115f0136f42

implode()

implode() is a reverse of explode(), means it joins an array into a sring. It has two parameters, first one is optional and second one is required.

Syntax:

imlode(string_separator, array);

Example:

<?php
$arr = array("Hello", "Dear", "How", "Are", "You");
echo implode(" ", $arr);
?>

Output:

Hello Dear How Are You

explode()

explode() explodes or break a string into an array. We can easily understand the functionality of this function by the name “explode”. explode() has three parameters, first 2 are required and third is optional.

Syntax:

explode(string_separator, $str, limit);

Example:

<?php
$mystr = "Hello Dear, How are you";
print_r(explode(" ", $mystr));
?>

Output:

Array ( [0] => Hello [1] => Dear, [2] => How [3] => are [4] => you )

echo()

This function helps to output more than one strings. Parameters in this function are optional.

count_chars()

This string function returns how many times a character (ASCII) appears in a string depending on the modes we specified.

By default, mode is 0 that returns an array with Key (ASCII Value) and Value (Number of Occurrences.

Mode 1 returns an array with same functionality as Mode 2, but it only lists appearance of characters which are greater than zero.

Mode 2 returns occurrence which are equal to zero.

Mode 3 returns string with difference characters used.

Mode 4 generates string of all unused characters.

Syntax:

count_chars($str, mode);

Example:

<?php
$mystr = "Hello Dear, How are you";
print_r(count_chars($mystr, 0));
print_r(count_chars($mystr, 1));
print_r(count_chars($mystr, 2));
echo count_chars($mystr, 3);
echo count_chars($mystr, 4);
?>