MySQL选择$id所在的位置 - MySQL select where $id

我有一个网站，上面有以下代码片段：

<?php
mysql_connect('localhost','root','password');
mysql_select_db('news');
$id_article = $_GET['newsid'];
$query = mysql_query('SELECT * FROM news WHERE id="$id_article"');
{
    echo '<div class="item"><h1><a href="read-news.php?newsid='.$query['id'].'">'.$query['subject'].'</a></h1><br />';
    echo $query['full_content'].'<br / >';
    echo date('D-M-Y', $query['date']).'<br / >';
    echo 'Posted by '.$id_article;
    echo '</div>'; 
}
?>

$id_article从以前的请求中获取id。$id_article有效，但$query无效。$query['***']仍为空白。我不知道为什么。请帮帮我！非常感谢！

您不会得到查询结果。使用如下：

<?php
   mysql_connect('localhost','root','password');
   mysql_select_db('news');
   $id_article = intval($_GET['newsid']);
   $query = mysql_query('SELECT * FROM news WHERE id=' . $id_article);
   if (mysql_num_rows($query) > 0)
   {
       $row = mysql_fetch_assoc($query);
       echo '<div class="item"><h1><a href="read-news.php?newsid='.$row['id'].'">'.$row['subject'].'</a></h1><br />';
       echo $row['full_content'].'<br / >';
       echo date('D-M-Y', $row['date']).'<br / >';
       echo 'Posted by '.$id_article;
       echo '</div>';
   } 
?>

提示：使用PDO或mysqli而不是mysql_函数！Mysql函数在新的php版本中被弃用/不受支持！

此外，在传递到您的查询之前，对您的输入进行疗养！

像这样使用

$result = mysql_query($query) or die(mysql_error());
$row = mysql_fetch_array($result) or die(mysql_error());
echo $row['id']. " - ". $row['date'];

您尚未使用mysql_fetch_assoc。使用如下：

$query = mysql_query('SELECT * FROM news WHERE id=' . $id_article);
$row = mysql_fetch_assoc($query);
if(count($row)>0)
{
     echo '<div class="item"><h1><a href="read-news.php?newsid='.$query['id'].'">'.$row['subject'].'</a></h1><br />';
     echo $row['full_content'].'<br / >';
     echo date('D-M-Y', $row['date']).'<br / >';
     echo 'Posted by '.$id_article;
     echo '</div>'; 
}

更改此代码

$query = mysql_query('SELECT * FROM news WHERE id="$id_article"');
{
    echo '<div class="item"><h1><a href="read-news.php?newsid='.$query['id'].'">'.$query['subject'].'</a></h1><br />';
    echo $query['full_content'].'<br / >';
    echo date('D-M-Y', $query['date']).'<br / >';
    echo 'Posted by '.$id_article;
    echo '</div>'; 
}

至

$sql = "SELECT * FROM news WHERE id = $id_article";
$query = mysql_query($sql);
while($result = mysql_fetch_assoc($query));
{
    echo '<div class="item"><h1><a href="read-news.php?newsid='.$result['id'].'">'.$result['subject'].'</a></h1><br />';
    echo $result['full_content'].'<br / >';
    echo date('D-M-Y', $result['date']).'<br / >';
    echo 'Posted by '.$id_article;
    echo '</div>'; 
}

您的代码中有很多错误mysql_query已折旧使用以下代码并检查错误

<?php
mysql_connect('localhost', 'root', 'password');
$conn = mysql_select_db('news');
$id_article = $_GET['newsid'];
if($query = mysqli_fetch_assoc(mysqli_query($conn,"SELECT * FROM news WHERE id=$id_article"))){ 
echo '<div class="item"><h1><a href="read-news.php?newsid=' . $query['id'] . '">' . $query['subject'] . '</a></h1><br />';
echo $query['full_content'] . '<br / >';
echo date('D-M-Y', $query['date']) . '<br / >';
echo 'Posted by ' . $id_article;
echo '</div>';
}
?>

试试这个。。

$id_article = $_GET['newsid'];
$query = "SELECT * FROM news WHERE id='$id_article'";
$query1=mysql_query($query);

您应该调用一个函数来获取查询返回的行。您正试图访问$查询而不是行。你的代码应该是这样的：

<?php
  mysql_connect('localhost','root','password');
  mysql_select_db('news');
  $id_article = $_GET['newsid'];
  $query = mysql_query('SELECT * FROM news WHERE id="$id_article"');
  if ($query) {    
    $row = mysql_fetch_assoc($query));
    echo '<div class="item"><h1><a href="read-news.php?newsid='. $row['id'].'">'. $row['subject'].'</a></h1><br />';
    echo $row['full_content'].'<br / >';
    echo date('D-M-Y', $row['date']).'<br / >';
    echo 'Posted by '.$id_article;
    echo '</div>'; 
  } else {
    $message  = 'Invalid query: ' . mysql_error() . "'n";
    $message .= 'Whole query: ' . $query;
    die($message);
  }
?>

您还可以查看mysql_result（）、mysql_fetch_array（）、mysql _fetch_row（）函数。