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count_chars

(PHP 4, PHP 5, PHP 7)

count_charsReturn information about characters used in a string

Description

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

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

Parameters

string

The examined string.

mode

See return values.

Return Values

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 not used characters is returned.

Changelog

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

Examples

Example #1 count_chars() example

<?php
$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";
}
?>

The above example will 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.

See Also

  • strpos() - Find the position of the first occurrence of a substring in a string
  • substr_count() - Count the number of substring occurrences

© 1997–2020 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.count-chars.php