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  • Drop down menu populated from MySQL that retains information if validation fails

I have a very simply form with multiple text boxes and a couple of drop downs. I am populating the drop downs from MySQL with the following code which works fine (I'm just showing the code for the drop down to keep things simple):

<?php
$hostname_sql = "localhost";
$database_sql = "database";
$username_sql = "user";
$password_sql = "password";
$sql = mysql_pconnect($hostname_sql, $username_sql, $password_sql) or trigger_error(mysql_error(),E_USER_ERROR);

$query_Recordset1 = "SELECT id, username FROM database ORDER BY username ASC";
$Recordset1 = mysql_query($query_Recordset1, $sql) or die(mysql_error());
$row_Recordset1 = mysql_fetch_assoc($Recordset1);
$totalRows_Recordset1 = mysql_num_rows($Recordset1);
?>

<html>
<head>
<title></title>
</head>

<body>
<form id="form1" name="form1" method="post" action="test.php">
<label>
<select name="form" id="form">
<?php
do {

?>
<option value="<?php echo $row_Recordset1['id']?>"><?php echo $row_Recordset1['username']?></option>
<?php
} while ($row_Recordset1 = mysql_fetch_assoc($Recordset1));
$rows = mysql_num_rows($Recordset1);
if($rows > 0) {
mysql_data_seek($Recordset1, 0);
$row_Recordset1 = mysql_fetch_assoc($Recordset1);
}
?>
</select>
</label>
<p>
<label>
<input type="submit" name="button" id="button" value="Submit" />
</label>
</p>
</form>
</body>
</html>
<?php
mysql_free_result($Recordset1);
?>

My question is... how can I get the drop down menu to retain the information selected by the user if form validation fails (for example he / she forgets to fill out a required text field) and so he / she is returned to the form with an error message.

With a static form, each option would be coded as follows:

<option value="Albania"<?php if ($_POST['location_currency'] == "Albania") echo " selected"; ?>>Albania</option>

I've tried combining it with the dynamic option value:

<option value="<?php echo $row_Recordset1['id']?>"><?php echo $row_Recordset1['username']?></option>

To produce:

<option value="<?php echo $row_Recordset1['id']?>"<?php if ($_POST['form1'] == "echo $row_Recordset1['id']") echo " selected"; ?>><?php echo $row_Recordset1['username']?></option>

without success. I just get a blank page. Tried escaping double quotes, that didn't work either.

    Your value is different than your innerHTML right.

    Here's how I like to handle this whole situation that I think you'll appreciate and like:

    $html = '<select name"select">';
foreach($dbOptions as $option)
{
	$htmlSel = NULL;
	if($option == $_REQUEST['select'])  $htmlSel = ' selected="selected"'; // NOTE: $_REQUEST catches both $_POST and $_GET passed variables
	$html .='<option value="' .$option. '"' .$htmlSel. '>' .stripslashes($option). '</option>';
}
$html .= '</select>';

    It's not tailored to your situation, but looking at your code, you'll be able to retro-fit just fine.

      This is such a common need with PHP forms that you really should consider using a function or class for this. More code but re-usable. Consider the following

      	/**
	 * selectMenu: auto generates a "select-one" or combo box form control
	 * with an optional default input. Options are input in fhe form of an associative array
	 * where the key is the label of the option and the value is the value attribute of
	 * the option. Attributes are input in the form of an associative array
	 * ie. 'class'=>'dropdown'. If set to "multiple" with attributes, $input can be an array of choices
	 *
	 * @param string $name
	 * @param array $op
	 * @param mixed $input
	 * @param array $attributes
	 * @return string
	 */
	function selectMenu($name,$op,$input='',$attributes=null)
	{
		if(!empty($name))
		{

		$attr = $attributes;
		if(is_array($attributes))
		{
			$attr = '';
			foreach($attributes as $key=>$aValue)
			{
				$attr .= " $key=\"$aValue\"";
			}
		}
		$multivalue = false;
		if(is_array($input) && isset($attributes['multiple']))
		{
			$multivalue = true;
		}
		$tag = "<select name=\"$name\"$attr>\n[options]</select>\n";
		$options = '';
		foreach($op as $key=>$value)
		{
			$selected = '';
			if(is_numeric($key))
			{
				$key = $value;
			}
			if($multivalue)
			{
				if(in_array($value,$input))
				{
					$selected = ' selected="selected"';
				}
			}
			else
			{
				if($value == $input)
				{
					$selected = ' selected="selected"';
				}
			}
			$options[] = "<option value=\"$value\"$selected>$key</option>";
		}
		if(!empty($options))
		{
			$tag = str_replace('[options]',"\t".implode("\n\t",$options)."\n",$tag);
		}
		else
		{
			$tag = str_replace('[options]',"\n",$tag);
		}
		return $tag;
	}
	else
	{
		return '';
	}
}

// use
$op = array('Steak'=>1,'Chicken'=>2,'Fish'=>3);
// $input can come from anywhere including database or $_GET or $_POST
$input = 2;
// attributes
$attributes = array('class'=>'dropdown');
$menu = selectMenu('mealchoice',$op,$input,$attributes);
echo($menu);
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