(PHP 5 >= 5.1.0, PHP 7, PHP 8)
Countable::count — 统计对象的元素个数
此函数没有参数。
int 形式的自定义计数。
示例 #1 Countable::count() 示例
<?php
class Counter implements Countable
{
private $count = 0;
public function count(): int
{
return ++$this->count;
}
}
$counter = new Counter;
for ($i = 0; $i < 10; ++$i) {
echo "I have been count()ed " . count($counter) . " times\n";
}
?>以上示例的输出类似于：
I have been count()ed 1 times I have been count()ed 2 times I have been count()ed 3 times I have been count()ed 4 times I have been count()ed 5 times I have been count()ed 6 times I have been count()ed 7 times I have been count()ed 8 times I have been count()ed 9 times I have been count()ed 10 times
Even though Countable::count method is called when the object implementing Countable is used in count() function, the second parameter of count, $mode, has no influence to your class method.
$mode is not passed to Countable::count:
<?php
class Foo implements Countable
{
public function count()
{
var_dump(func_get_args());
return 1;
}
}
count(new Foo(), COUNT_RECURSIVE);
?>
var_dump output:
array(0) {
}