count_chars()

(PHP 4, PHP 5, PHP 7)

返回字符串所用字符的信息

说明

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。

参数

需要统计的字符串。

参见返回的值。

返回值

根据不同的$mode，count_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。

范例

Example #1count_chars()示例

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()查找字符串首次出现的位置
• substr_count()计算字串出现的次数

If you have problems using count_chars with a multibyte string, you can change the page encoding. Alternatively, you can also use this mb_count_chars version of the function. Basically it is mode "1" of the original function.