如何解决每个PHP已弃用的功能

Question

使用PHP 7.2，each不推荐使用。文件说：

警告此功能自PHP 7.2.0起已废弃。非常不鼓励依赖此功能。

如何更新我的代码以避免使用它？这里有些例子：

$ar = $o->me;

reset($ar);

list($typ, $val) = each($ar);

$out = array('me' => array(), 'mytype' => 2, '_php_class' => null);

$expected = each($out);

for(reset($broken);$kv = each($broken);) {...}

list(, $this->result) = each($this->cache_data);

// iterating to the end of an array or a limit > the length of the array

$i = 0;

reset($array);

while( (list($id, $item) = each($array)) || $i < 30 ) {

    // code

    $i++;

}

Answer 1

对于前两个示例案例，您可以使用key()和current()分配所需的值。$ar = $o->me;&nbsp; &nbsp;// reset isn't necessary, since you just created the array$typ = key($ar);$val = current($ar);$out = array('me' => array(), 'mytype' => 2, '_php_class' => null);$expected = [key($out), current($out)];在这些情况下，您可以使用next()以后推进光标，但如果其余代码不依赖于此，则可能没有必要。对于第三种情况，我建议只使用foreach()循环而$kv在循环内部分配。&nbsp; &nbsp; foreach ($broken as $k => $v) {&nbsp; &nbsp; &nbsp; &nbsp; $kv = [$k, $v];&nbsp; &nbsp; }对于第四种情况，看起来密钥被忽略list()，因此您可以分配当前值。&nbsp; &nbsp; $this->result = current($this->cache_data);与前两种情况一样，可能需要next()根据代码的其余部分如何与之交互来推进光标$this->cache_data。第五个可以用for()循环代替。&nbsp; &nbsp; reset($array);&nbsp; &nbsp; for ($i = 0; $i < 30; $i++) {&nbsp; &nbsp; &nbsp; &nbsp; $id = key($array);&nbsp; &nbsp; &nbsp; &nbsp; $item = current($array);&nbsp; &nbsp; &nbsp; &nbsp; // code&nbsp; &nbsp; &nbsp; &nbsp; next($array);&nbsp; &nbsp; }

Answer 2

你可以each()使用key（），current（）和next（）创建自己的函数。然后用该函数替换你的调用，如下所示：<?phpfunction myEach(&$arr) {&nbsp; &nbsp; $key = key($arr);&nbsp; &nbsp; $result = ($key === null) ? false : [$key, current($arr), 'key' => $key, 'value' => current($arr)];&nbsp; &nbsp; next($arr);&nbsp; &nbsp; return $result;}1。$ar = $o->me;reset($ar);list($typ, $val) = myEach($ar);2。$out = array('me' => array(), 'mytype' => 2, '_php_class' => null);$expected = myEach($out);3。for(reset($broken);$kv = myEach($broken);) {...}

Answer 3

reset($array);while (list($key, $value) = each($array)) {UPDATEreset($array);foreach($array as $key => $value) {