如何在while循环中从动态生成的文本框中发布多个条目

Question

please i am currently working on a school result computation project in php. I have a page that gets all the students that enrolled for a particular subject. A while loop generates three textboxes against each student's name(CA1, CA2, and Exam). Please can anyone help me with a solution?? When the form is submitted only the last entry enters the database. Below is my code.

<?php
session_start();
include 'header_staff.php';

$subject=$_POST['subject'];
$user_id=$_SESSION['user_id'];
$get=mysql_query("SELECT * FROM staffrecord WHERE user_id='$user_id'",$conn);
$go=mysql_fetch_array($get);
$class=$go['class_id'];
$sql=mysql_query("SELECT * FROM student_enrollment WHERE class_id='$class' AND subject_id='$subject'",$conn);
echo '<form action="submitrslt.php" method="post">';
while($subj=mysql_fetch_array($sql)){
echo $subj['name'];
echo '<input type="text" name="ca1" />';
echo '<input type="text" name="ca2" />';
echo '<input type="text" name="exam" /><br><br>';
}
echo '<input type="submit" value="submit" />';

?>

Answer 1

The solution to your problem is to use your input arrays by simply adding [] to the input names:

while($subj=mysql_fetch_array($sql)){
  echo $subj['name'];
  echo '<input type="text" name="ca1[]" />';
  echo '<input type="text" name="ca2[]" />';
  echo '<input type="text" name="exam[]" /><br><br>';
}

Further, you can use the primary key of your table as the index in each iteration (let's suppose this would be $subj['id'], but if it is more meaningful in your case, you can also use $subj['name'] as the index):

while($subj=mysql_fetch_array($sql)){
  echo $subj['name'];
  echo '<input type="text" name="ca1[<?php echo $subj['id'] ?>]" />';
  echo '<input type="text" name="ca2[<?php echo $subj['id'] ?>]" />';
  echo '<input type="text" name="exam[<?php echo $subj['id'] ?>]" /><br><br>';
}

This way you can easily identify values from the resulting array after the post.

PS: Be sure you never trust user input without verifying or sanitizing it - make sure $_POST['subject'] is numeric. You can find plenty of useful tips on how to achieve this.