php地址和值引用

function test(){
        $datas = [100,200,300,400];
        foreach ($datas as &$item){
 
        }
        foreach ($datas as $item){
 
        }
        dump($datas);
    }

function test(){ $datas = [100,200,300,400]; foreach ($datas as &$item){ } foreach ($datas as $item){ } dump($datas); }

    function testaa(){
        $datas = [100,200,300,400];
        foreach ($datas as &$item){
 
        }
 
        foreach ($datas as $item){
            dump($datas);
        }
    }

function testaa(){ $datas = [100,200,300,400]; foreach ($datas as &$item){ } foreach ($datas as $item){ dump($datas); } }

    function test(){
        $datas = [100,200,300,400];
        foreach ($datas as &$item){
 
        }
        foreach ($datas as $itemOrder){
 
        }
        dump($datas);
    }

function test(){ $datas = [100,200,300,400]; foreach ($datas as &$item){ } foreach ($datas as $itemOrder){ } dump($datas); }

    function test(){
        $datas = [100,200,300,400];
        foreach ($datas as &$item){
 
        }
        unset($item);  // 取消引用
        foreach ($datas as $itemOrder){
 
        }
        dump($datas);
    }

function test(){ $datas = [100,200,300,400]; foreach ($datas as &$item){ } unset($item); // 取消引用 foreach ($datas as $itemOrder){ } dump($datas); }