(PHP 4, PHP 5, PHP 7, PHP 8)
count_chars — 返回字符串所用字符的信息
統計 string
中每個(gè)字節值（0..255）出現的次數，使用多種模式返回結果。
string需要統計的字符串。
mode參見(jiàn)返回的值。
根據不同的 mode，count_chars()
返回下列不同的結果：
示例 #1 count_chars() 示例
<?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";
}
?>
以上例程會(huì )輸出：
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.