PHP Manual: count_chars

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count_chars

(PHP 4, PHP 5)

count_chars -- Return information about characters used in a string

Description

mixed count_chars ( string string [, int mode] )

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: The optional parameter mode defaults to 0.

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 used byte-values is returned.
4 - a string containing all not used byte-values is returned.

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.