Countable::count()
(PHP 5 >= 5.1.0, PHP 7)
统计一个对象的元素个数
说明
abstract public Countable::count(void): int
当使用count()函数作用于一个实现了Countable的对象时这个方法会被执行.
参数
此函数没有参数。
返回值
The custom count as an integer.
Note:The return value is cast to an integer.
范例
Countable::count() example
<?php class myCounter implements Countable { public function count() { static $count = 0; return ++$count; } } $counter = new myCounter; for($i=0; $i<10; ++$i) { echo "I have been count()ed " . count($counter) . " times\n"; } ?>
以上例程的输出类似于:
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) { }