Programmatically generating a drop-down menu - php

Question

I have a drop down menu below:
$form = "
<form action='" . htmlentities($_SERVER["PHP_SELF"]) . "' method='post'>
<table>
<tr>
<td><select name='year' id='yearDrop'>
<option value=''></option>
<option value='$getyear[1]'>1</option>
<option value='$getyear[2]'>2</option>
<option value='$getyear[3]'>3</option>
<option value='$getyear[4]'>4</option>
<option value='$getyear[5]'>5</option>
<option value='$getyear[6]'>6</option>
<option value='$getyear[7]'>7</option>
<option value='$getyear[8]'>8</option>
<option value='$getyear[9]'>9</option>
<option value='$getyear[10]'>10</option>
</select></td>
</tr>
</table>
</form>
";
Notice the drop down menus are in a php varaible in a form. My question is: "is there a much better and shorter method of displaying the drop down menu above?". Maybe by using some sort of loop to loop through each value and give each option the same value attribute?
I want to use getyear in order to fit in a simple if statement:
if ($getyear){
echo "year is chosen";
}else{
$errormsg = "You must enter in Student's current Academic Year to Register";
}
UPDATE:
<?php
$getyear = (isset($_POST['year'])) ? $_POST['year'] : '';
$errormsg = (isset($errormsg)) ? $errormsg : '';
$min_year = 1;
$max_year = 10;
$years = range($min_year, $max_year); // returns array with numeric values of 1900 - 2012
$yearHTML = '';
$yearHTML .= '<select name="year" id="yearDrop">'.PHP_EOL;
$yearHTML .= '<option value="">Please Select</option>'.PHP_EOL;
foreach ($years as $year) {
$yearHTML .= "<option>$year</option>".PHP_EOL; // if no value attribute, value will be whatever is inside option tag, in this case, $year
}
$yearHTML .= '</select>';
if( (isset($_POST['registerbtn']))){
$getyear = $_POST['year'];
if (!in_array($getyear , $years)){
echo "year is chosen";
}else{
$errormsg = "You must enter in Student's current Academic Year to Register";
}
}
$form = "
<form action='" . htmlentities($_SERVER["PHP_SELF"]) . "' method='post'>
<table>
<tr>
<td></td>
<td id='errormsg'>$errormsg</td>
</tr>
<tr>
<td>Year:</td>
<td>{$yearHTML}</td>
<td><input type='text' name='year' value='$getyear' /></td>
</tr>
<tr>
<td></td>
<td><input type='submit' value='Register' name='registerbtn' /></td>
</tr>
</table>
</form>";
echo $form;
?>

Answer 1

The foreach loop is extremely beneficial when looping over arrays and performing operations on their values.
foreach control structure
<?php
// reference values for output and for validation later
$min_year = 1900; // using as an example
$max_year = 2012;
$years = range($min_year, $max_year); // returns array with numeric values of 1900 - 2012
// for HTML output
if (empty($_POST)) { // display form
$html = '';
foreach ($years as $year) {
$html .= "<option>$year</option>"; // if no value attribute, value will be whatever is inside option tag, in this case, $year
}
// output HTML
echo $html;
} else { // process form
$chosen_year = isset($_POST['year']) ? $_POST['year'] : "";
if (!in_array($chosen_year , $years) { // year is invalid
$errormsg = "You must enter in Student's current Academic Year to Register";
} else { // year is chosen
echo 'year is chosen';
}
}

Answer 2

This file will generate the select options automatically, and give you an easy place to do further processing.
function process_form(){
if(!isset($_POST['year']) || !is_numeric($_POST['year'])){
// Form invalid
return false;
}
$year = $_POST['year'];
// Perform actions - save to database, etc..?
// Form valid
return true;
}
$error = false;
if($_SERVER['REQUEST_METHOD'] == 'POST'){
// Form submitted
$result = process_form();
if($result){
?>
<p>Valid year selected</p>
<?php
exit;
}
$error = true;
}
?>
<form action="" method="post">
<?php if($error){ ?>
<p class="error">You must select the student's current academic year to register</p>
<?php } ?>
<label for="select_year">Academic Year:</label>
<select name="year" id="select_year">
<option value=""></option>
<?php for($year = $start_year; $year <= $end_year; $year++){ ?>
<option value="<?php echo $year;?>"><?php echo $year;?></option>
<?php } ?>
</select>
<button type="submit">Register</button>
</form>