(PHP 5 >= 5.1.0, PHP 7, PHP 8)
Countable::count — 统计一个对象的元素个数
此函数没有参数。
The custom count as an integer.
Note:
The return value is cast to an integer.
Example #1 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) {
}