虽然循环 PHP get_result 不起作用

我正在尝试使用 MySQl 准备好的语句从数据库中获取行并获得结果.然而，这是行不通的.

请有人知道我哪里出错了吗?我已经尝试了几个小时的解决方案，但我无法让它发挥作用.该页面不会加载，就好像查询失败一样.

 $tag = trim($_GET['tag']);$stmt = $mysqli->prepare('SELECT posts.* FROM tags JOIN posts ON posts.id = tags.post_id WHERE tag = ?');$stmt->bind_param('s', $tag);$stmt->execute();$stmt->store_result();$result = $stmt->get_result();while ($row = $result->fetch_assoc()) {回声 $row['tag'];}$stmt->free_result();$stmt->close();

解决方案

试试这个:

$stmt = $mysqli->prepare('SELECT posts.id FROM tags JOIN posts ON posts.id = tags.post_id WHERE tag = ?');...$stmt->bind_result($id);而 ($stmt-> fetch()) {//var_dump 整行以确保您期望的密钥可用var_dump($id);}

更新

如果你想做一个选择 *，而不是单独指定每一列，看看这个 post(不是接受的答案，而是得分最高的答案).否则，我强烈建议您查看 PDO，因为它使这些基本的读取操作变得更加容易.>

I am trying to get rows from the database using MySQl prepared statements and get result. However this is not working.

Please can someone see where I am going wrong? I have been trying solutions for hours but I can't get it to work. The page just doesn't load as if the query has failed.

 $tag = trim($_GET['tag']);

 $stmt = $mysqli->prepare('SELECT posts.* FROM tags JOIN posts ON posts.id = tags.post_id WHERE tag = ?');
 $stmt->bind_param('s', $tag);
 $stmt->execute();
 $stmt->store_result();
 $result = $stmt->get_result();

 while ($row = $result->fetch_assoc()) {

     echo $row['tag'];

 }      

 $stmt->free_result();
 $stmt->close();

解决方案

Try this:

$stmt = $mysqli->prepare('SELECT posts.id FROM tags JOIN posts ON posts.id = tags.post_id WHERE tag = ?');

...

$stmt->bind_result($id);    

while ($stmt->fetch()) {

    // var_dump entire row to ensure the key you expect is avail
    var_dump($id);

}

Upate

If you want to do a select *, vs having to specify EVERY column individually, check out this post (not the accepted answer, but the highest scoring answer). Otherwise I strongly urge you to check out PDO, as it makes these basic read ops much easier.