PHP 閉包，簡易記數工廠

閉包的使用

php5.3開始支援閉包

// 簡易的計數器工廠模式

function counterFactory() {

    $counter = 1;

    return function() use(&$counter) {

        return $counter++;

    };

}

$counter1 = counterFactory();

$counter2 = counterFactory();

echo "counter1: " . $counter1() . "<br />";

echo "counter1: " . $counter1() . "<br />";

echo "counter1: " . $counter1() . "<br />";

echo "counter1: " . $counter1() . "<br />";

echo "counter2: " . $counter2() . "<br />";

echo "counter2: " . $counter2() . "<br />";

echo "counter2: " . $counter2() . "<br />";

// counter1: 1

// counter1: 2

// counter1: 3

// counter1: 4

// counter2: 1

// counter2: 2

// counter2: 3