Question

below I have a form where it contains a couple of text inputs, a drop down menu, and messages for validation and success:

<?php

$getyear = (isset($_POST['year'])) ? $_POST['year'] : '';

$sql = "SELECT CourseId, CourseName FROM Course ORDER BY CourseId";

$sqlstmt=$mysqli->prepare($sql);

$sqlstmt->execute();

$sqlstmt->bind_result($dbCourseId, $dbCourseName);

$courses = array(); // easier if you don't use generic names for data

$courseHTML = "";
$courseHTML .= '<select name="course" id="coursesDrop">'.PHP_EOL;
$courseHTML .= '<option value="">Please Select</option>'.PHP_EOL;

while($sqlstmt->fetch())
{
    $course = $dbCourseId;
    $coursename = $dbCourseName;
    $courseHTML .= "<option value='".$course."'>" . $course . " - " . $coursename . "</option>".PHP_EOL;

}

$courseHTML .= '</select>';

if((isset($_POST['registerbtn'])))
{
    $getfirstname = $_POST['firstname'];
    $getsurname = $_POST['surname'];
    $getcourse = $_POST['course'];


    if ($getfirstname)
    {
        if ($getsurname)
        {
            if ($getcourse)
            {
                // don't use $mysqli->prepare here
                $query = "SELECT StudentUsername FROM Student WHERE StudentUsername = ?";
                // prepare query
                $stmt=$mysqli->prepare($query);
                // You only need to call bind_param once
                $stmt->bind_param("s",$getid);
                // execute query
                $stmt->execute();
                // get result and assign variables (prefix with db)
                $stmt->bind_result($dbStudentUsername);
                //get number of rows
                $stmt->store_result();
                $numrows = $stmt->num_rows();


                if ($numrows == 1)
                {
                    $errormsg = "<span style='color: green'>Student has been Registered</span>";
                    $getfirstname = "";
                    $getsurname = "";
                    $getcourse = "";
                }
                else
                {
                    $errormsg = "An error has occured, Student has not been Registered";
                }
            }
            else
            {
                $errormsg = "You must select the Student's Course to Register";
            }
        }
        else
        {
            $errormsg = "You must enter in Student's Surname to Register";
        }

    }
    else
    {
        $errormsg = "You must enter in Student's First Name to Register";
    }
}

$form = "
<form action='" . htmlentities($_SERVER["PHP_SELF"]) . "' method='post'>
<table>
<tr>
<td></td>
<td id='errormsg'>$errormsg</td>
</tr>
<tr>
<td>First Name:</td>
<td><input type='text' name='firstname' value='$getfirstname' /></td>
</tr>
<tr>
<td>Surname:</td>
<td><input type='text' name='surname' value='$getsurname' /></td>
</tr>
<tr>
<td>Course:</td>
<td>{$courseHTML}</td>
</tr>
<tr>
<td></td>
<td><input type='submit' value='Register' name='registerbtn' /></td>
</tr>
</table>
</form>";

echo $form;

?>

Now the problem I am having is actually with the drop down menu.

If the succes message appears, then it displays the “Please Select” option for the course drop down menu which is fine, but if the user submits the form and a validation message appears, the drop down menu goes back to the “Please Select” option. I want it to stay with the last option the user has selected. How can this be achieved with the code above it is is possible?

Answer 1

Change the following line:

$courseHTML .= "<option value='".$course."'>" . $course . " - " . $coursename . "</option>".PHP_EOL;

To this:

if (isset($_POST['course']) && $course == $_POST['course'])
{
    $courseHTML .= "<option value='".$course."' selected='selected'>" . $course . " - " . $coursename . "</option>".PHP_EOL;
}
else
{
    $courseHTML .= "<option value='".$course."'>" . $course . " - " . $coursename . "</option>".PHP_EOL;
}

What this does is checks if the current $course is equal to the $_POST['course']. If it is, it sets the option to selected.

Edit 1

You can check if your form submissions are valid, and that the form is going to pass later on with the following:

$validSubmission = isset($_POST['registerbtn']) && $_POST['firstname'] && $_POST['surname'] && $_POST['course'];

while($sqlstmt->fetch())
{
    $course = $dbCourseId;
    $coursename = $dbCourseName;
    if (!$validSubmission && isset($_POST['course']) && $course == $_POST['course'])
    {
        $courseHTML .= "<option value='".$course."' selected='selected'>" . $course . " - " . $coursename . "</option>".PHP_EOL;
    }
    else
    {
        $courseHTML .= "<option value='".$course."'>" . $course . " - " . $coursename . "</option>".PHP_EOL;
    }
}