Question

如果项目中有条件，我已经嵌套了，但是我有问题；

if(isset($_GET['q']) && isset($_GET['t'])) {
  $query = $_GET['q'];
  $type = $_GET['t'];
  $none_key = FALSE;

  if($type = 'singer') {
      $singers = $connect->query("SELECT * FROM lyrica_singers WHERE singer_name LIKE '%$query%'");
      $control = $singers->rowCount();

      if($control > 0)  {
        $on_page = 24;
        $number_singers = $singers->rowCount();
        $number_page = ceil($number_singers/$on_page);

        $page = isset($_GET['p']) ? (int) $_GET['p'] : 1;
        if ($page < 1) $page = 1;
        if ($page>$number_page) $page = $number_page;

        $limit = ($page - 1) * $on_page;

        $singers = $connect->query("SELECT * FROM lyrica_singers WHERE singer_name LIKE '%$query%' ORDER BY singer_name ASC LIMIT ".$limit.",".$on_page);
        $singer_key = TRUE;
      } else {
        $none_key = TRUE;
      }
    }

    if($type = 'song') {
      $songs = $connect->query("SELECT * FROM lyrica_songs WHERE song_name LIKE '%$query%'");
      $control = $songs->rowCount();

      if($control > 0)  {
        $on_page = 24;
        $number_songs = $songs->rowCount();
        $number_page = ceil($number_songs/$on_page);

        $page = isset($_GET['p']) ? (int) $_GET['p'] : 1;
        if ($page < 1) $page = 1;
        if ($page>$number_page) $page = $number_page;

        $limit = ($page - 1) * $on_page;

        $songs = $connect->query("SELECT * FROM lyrica_songs WHERE song_name LIKE '%$query%' ORDER BY song_name ASC LIMIT ".$limit.",".$on_page);
        $song_key = TRUE;
      } else {
        $none_key = TRUE;
      }
    }
} else {
  $key = TRUE;
}

运行代码时，我希望如果'control'变量之一大于0，则'none_key'变量必须等于0。'type'变量为'song'时没有问题但是如果'type'变量是'singer'，那么'none_key'变量将显示1，我认为它正在运行第二个if块，并且由于第二个'control'变量不大于零而变为'none_key'1。

Answer 1

这是一个分配，它将$type设置为值singer：

if ($type = 'singer') {

您要进行比较，它会检查$type是否等于值singer：

if ($type == 'singer') {

[编辑] 有些人喜欢用变量last来编写这种语句。这通常称为“尤达条件”：

if ('singer' == $type) {

这样，如果您搞砸了，只使用一个=，则会出现错误。

如果条件不起作用则嵌套

1 个答案: