count_chars

(PHP 4, PHP 5)

count_chars --  返回字符串所用字符的信息

描述

mixed count_chars ( string string [, int mode] )

统计 string 中每个字节值(0..255)出现的次数,使用多种模式返回结果。可选参数 mode 默认值为 0。根据不同的 modecount_chars() 返回下列不同的结果:

例子 1. count_chars() 示例

<?php

$data
= "Two Ts and one F.";

$result = count_chars($data, 0);

for (
$i=0; $i < count($result); $i++) {
   if (
$result[$i] != 0)
       echo
"There were $result[$i] instance(s) of \"" , chr($i) , "\" in the string.\n";
}

?>

下边为示例输出:

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.

参见 strpos()substr_count()