count_chars 返回字符串所用字符的信息


count_chars

(PHP 4, PHP 5)

count_chars返回字符串所用字符的信息

说明

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:

  • 0 - 以所有的每个字节值作为键名,出现次数作为值的数组。
  • 1 - 与 0 相同,但只列出出现次数大于零的字节值。
  • 2 - 与 0 相同,但只列出出现次数等于零的字节值。
  • 3 - 返回由所有使用了的字节值组成的字符串。
  • 4 - 返回由所有未使用的字节值组成的字符串。

Example #1 count_chars() 示例

<?php
$data 
"Two Ts and one F.";

foreach (
count_chars($data1) as $i => $val) {
    echo 
"There were $val instance(s) of "" chr($i) , "" in the string. ";
}
?>

以上例程会输出:

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()


«  count
» crc32
快速导航

Copyright © 2016 phpStudy | 皖ICP备18014864号-4