select options not displaying using functions - php

Question

I am trying to displays value of selects options dynamically in PHP. Basically user creates those options awhich are stored in database and then I am trying to fetch this at different place. for this purpose i wrote the below function:
function fetch_acad_yr($conn) {
$query = "SELECT a.fk_acadyear_id as acadyearid,b.acad_year as acadyear FROM tbl_admparam a inner join list_acad_years b on a.fk_acadyear_id = b.pk_acad_year_id";
$stmt = $conn->prepare($query);
if ($stmt->execute()) {
foreach ($stmt as $row) {
?>
<option value="<?php echo $row['acadyearid'] ?>"><?php echo $row['acadyear'] ?></option>
<?php
}
}
}
then in html i called this function
<select class="form-control" id="acad_period" name="acad_period" required>
<option value="">Please select...</option>
<?php fetch_acad_yr($conn); ?>
</select>
But the options doent show any values it simply come blank and is not dispalying the values stored in database. I tried running the query separately and the query is returning the desired result

Answer 1

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "dbname";
// Create connection
$con = new mysqli($servername, $username, $password,$dbname);
if ($con->connect_error)
{
die("Connection failed: " . $con->connect_error);
}
?>
<select name="acad_period" required="">
<option value="0">Select</option>
<?php
$s= "SELECT a.fk_acadyear_id as acadyearid,b.acad_year as acadyear FROM tbl_admparam a inner join list_acad_years b on a.fk_acadyear_id = b.pk_acad_year_id";
$ex= $con->query($s);
if (!$ex)
{
echo("Error description: " . mysqli_error($con));
}
else
{
while ($f= $ex->fetch_assoc())
{
?>
<option value="<?php echo $f['acadyearid'] ?>"><?php echo $f['acadyear'] ?></option>
<?php
# code...
}
}
?>
</select>

Answer 2

Make sure you have the right connection and the data coming in the query result.
Basic php mysql code I used was the below and it worked. You make change it to pdo or propel and get the result. But the usage is same with while or for loop.
$conn = mysql_connect($host, $username, $pass);
mysql_select_db($dbname, $conn);
echo "<pre>";
echo "<select>";
fetch_acad_yr($conn);
echo "<\select>";
function fetch_acad_yr($conn) {
$query = "SELECT a.fk_acadyear_id as acadyearid,b.acad_year as acadyear FROM tbl_admparam a inner join list_acad_years b on a.fk_acadyear_id = b.pk_acad_year_id";
$res = mysql_query($query);
while($row = mysql_fetch_assoc($res)){
?>
<option value="<?php echo $row['acadyearid'] ?>"><?php echo $row['acadyear'] ?></option>
<?php
}
}
?>
Works for me.