php - 在 foreach 循环中使用 SQL 结果

Question

我觉得我在这里遗漏了一些非常明显的东西，我正在尝试获取 SQL 查询的结果，然后在循环中使用它们。我觉得我错过了一些非常明显的东西，无论有没有注释行，我都试过了。

<?php
$sentToID = $_SESSION['userID'];

$query = "SELECT *
          FROM messages
          WHERE sentToID = '$sentToID'";

$results = mysql_query($query);
//$userData = mysql_fetch_array($results, MYSQL_ASSOC);

foreach ($results as $result){
    $messageID = $result['messageID'];
    $sentFromID = $result['sentFromID'];
    $subject = $result['subject'];
    $body = $result['body'];
    $dateTime = $result['dateTime'];

    $query = "SELECT usertype 
              FROM user
              WHERE userID = '$sentFromID'";
    $messageResult = mysql_query($query);
    $messageData = mysql_fetch_array($messageResult, MYSQL_ASSOC);

    $usertype = $messageData['usertype'];

    $query = "SELECT * 
              FROM $usertype
              WHERE userID = '$sentFromID'";

    $messageResult = mysql_query($query);
    $messageData = mysql_fetch_array($messageResult, MYSQL_ASSOC);

    if ($usertype == "jobseeker"){
        $forname = $messageData['forename'];
        $surname = $messageData['surname'];
        echo "<div><p>" . $forename . " " . $surname . "</p>
              <p>Subject: " . $subject ."</p>
              <p>Body: " . $body . "</p></div>";
    }
    if ($usertype == "employer"){
        $forname = $messageData['forename'];
        $surname = $messageData['surname'];
        $companyName = $messageData['companyName'];

        echo "<div><p>" . $forename . " " . $surname . " - " . $companyName . "</p>
              <p>Subject: " . $subject ."</p>
              <p>Body: " . $body . "</p></div>";
    }
}
?>

任何帮助将不胜感激

Answer 1

您必须先将结果提取到一个数组中。看起来您开始执行此操作但将其注释掉了。

$results = mysql_query($query);
//$userData = mysql_fetch_array($results, MYSQL_ASSOC);

$resultset = array();
while ($row = mysql_fetch_array($results)) {
  $resultset[] = $row;
}

// $resultset now holds all rows from the first query.
foreach ($resultset as $result){
 //... etc...