Question

我上次查询需要帮助。当我提交时，我想显示该特定LRN的所有列。我无法让它发挥作用。当我点击提交时，它没有显示任何内容。提前谢谢。

<?php

$conn = new mysqli('localhost', 'root', 'user, 'pwd') 
or die ('Cannot connect to db');

$result = $conn->query("select * from students");

echo "<html>";
echo "<body>";
echo "<form method = POST>";
echo "<select name = 'Students' onchange=this.form.submit()>";

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

              unset($LRN, $First, $Last);
              $LRN = $row['LRN'];
              $First = $row['First_Name'];
              $Last = $row['Last_Name']; 
              echo '<option value="'.$LRN.'">'.$Last.', '.$First.'</option>';

}

echo "</select>";
echo "<input type='submit' name='submit' value='Show'>";
echo "</form>";

$submit = filter_input(INPUT_POST,'submit');
$students = filter_input(INPUT_POST,'Students');


if(isset($submit)) {
    $tae = $conn->query('select * from students WHERE LRN=.$Students.');
    echo $tae;
}
echo "</body>";
echo "</html>";
?>

从下拉菜单查询结果

0 个答案: