count_chars()

count_chars() — Return information about characters used in a string.

Built-in function of PHP 8.5. The manual lists it as available in PHP 4, PHP 5, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.

What it does

Counts the number of occurrences of every byte-value (0..255) in string and returns it in various ways.

Signature

count_chars(string $string, int $mode = 0): array|string

Parameters

ParameterTypeWhat it takes
$stringstringThe examined string.
$modeintSee return values.

Return value

Depending on mode count_chars() returns one of the following: 0 - an array with the byte-value as key and the frequency of every byte as value. 1 - same as 0 but only byte-values with a frequency greater than zero are listed. 2 - same as 0 but only byte-values with a frequency equal to zero are listed. 3 - a string containing all unique characters is returned. 4 - a string containing all unused characters is returned. 0 - an array with the byte-value as key and the frequency of every byte as value. 1 - same as 0 but only byte-values with a frequency greater than zero are listed. 2 - same as 0 but only byte-values with a frequency equal to zero are listed. 3 - a string containing all unique ...

Example

A runnable snippet:

$data = "Two Ts and one F."; foreach (count_chars($data, 1) as $i => $val) { echo "There were $val instance(s) of \"" , chr($i) , "\" in the string.\n"; }

Output:

There were 4 instance(s) of " " in the string. There were 1 instance(s) of "." in the string. There were 1 instance(s) of "F" in the string. There were 2 instance(s) of "T" in the string. There were 1 instance(s) of "a" in the string. There were 1 instance(s) of "d" in the string. There were 1 instance(s) of "e" in the string. There were 2 instance(s) of "n" in the string. There were 2 instance(s) of "o" in the string. There were 1 instance(s) of "s" in the string. There were 1 instance(s) of "w" in the string.

Changelog

VersionChange
8.0.0Prior to this version, the function returned false on failure.

See also

strpos(), substr_count()

All PHP 8.5 built-in functions

Reference card built from the PHP manual page count_chars() (PHP documentation, CC BY 3.0). The page is generated from the manual, so the wording of the parameter and return value text follows php.net.