You're trying to mix PDO and mysqli functions which isnt going to work and you have no name tag associated with any of your form inputs which php needs to suck out the information from the form fields.
There's plenty wrong with the code you have posted. Have a look at the working code below which uses mysqli. Your database table (itemdatabase) needs to have the columns: floor, room, item, brand, quality set as varchar(100) plus an id column set as INT(11) and should be the primary auto-increment identifier.
Obviously you need to replace YOUR-PASSWORD in the database connection string:
<?php $conn = new mysqli('localhost' , 'root' , 'YOUR-PASWORD' , 'travelodgehotel');
//make sure special characters output correctly
mysqli_query($conn, "SET NAMES 'UTF8'") or die("ERROR: ". mysqli_error($conn));
?>
<?php
if(isset($_POST['submit'])) {
$floor = $conn->real_escape_string($_POST['floor']);
if(empty($floor)) {
$error['floor'] = "Please provide floor information";
}
$room = $conn->real_escape_string($_POST['room']);
if(empty($room)) {
$error['room'] = "Please provide room information";
}
$item = $conn->real_escape_string($_POST['item']);
if(empty($item)) {
$error['item'] = "Please provide item information";
}
$brand = $conn->real_escape_string($_POST['brand']);
if(empty($brand)) {
$error['brand'] = "Please provide brand information";
}
$quality = $conn->real_escape_string($_POST['quality']);
if(empty($quality)) {
$error['quality'] = "Please provide quality information";
}
if(!$error) {
$conn->query("INSERT INTO itemdatabase
(floor,
room,
item,
brand,
quality
)
VALUES
('$floor',
'$room',
'$item',
'$brand',
'$quality')");
echo "<h5>Successfully Inserted</h5>";
}
else {
echo "<ul>";
foreach($error as $error) {
echo "<li>$error</li>";
}
echo "</ul>";
}
}
?>
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
<title>jQuery Mobile: Theme Download</title>
</head>
<body>
<div data-role="page" data-theme="a">
<div data-role="header" data-position="inline">
<h1><img src="themes/images/TravelodgeHotelLogo.png" alt="" style="width:123.5px;height:26.25px;"></h1>
<div data-role="navbar">
<ul>
<li><a href="index.html" data-icon="home" class="ui-btn-active">Home</a></li>
<li><a href="spreadsheet.html" data-icon="grid">Spreadsheet</a></li>
<li><a href="information.html" data-icon="info">Information</a></li>
<li><a href="settings.html" data-icon="gear">Settings</a></li>
</ul>
</div>
</div>
<div data-role="content" data-theme="a">
<form action="index.php" method="post">
<div data-role="fieldcontain">
<select name="floor" name="floor" id="floor" data-native-menu="false">
<option value="<?php
if(!isset($error['floor'])) {
echo $floor; } ?>" selected><?php if($_POST['floor'] == "") {
echo "Floor"; } else { echo $floor; }?></option>
<option value="Floor 1">Floor 1</option>
<option value="Floor 2">Floor 2</option>
<option value="Floor 3">Floor 3</option>
<option value="Floor 4">Floor 4</option>
<option value="Floor 5">Floor 5</option>
<option value="Floor 6">Floor 6</option>
<option value="Floor 7">Floor 7</option>
<option value="Floor 8">Floor 8</option>
<option value="Floor 9">Floor 9</option>
</select>
</div>
<div data-role="fieldcontain">
<select name="room" name="room" id="room" data-native-menu="false">
<option value="<?php
if(!isset($error['room'])) {
echo $room; } ?>" selected><?php if($_POST['room'] == "") {
echo "Room"; } else { echo $room; }?></option>
<option value="Room 1">Room 1</option>
<option value="Room 2">Room 2</option>
<option value="Room 3">Room 3</option>
<option value="Room 4">Room 4</option>
<option value="Room 5">Room 5</option>
<option value="Room 6">Room 6</option>
<option value="Room 7">Room 7</option>
<option value="Room 8">Room 8</option>
<option value="Room 9">Room 9</option>
<option value="Room 10">Room 10</option>
<option value="Room 11">Room 11</option>
<option value="Room 12">Room 12</option>
<option value="Room 13">Room 13</option>
<option value="Room 14">Room 14</option>
<option value="Room 15">Room 15</option>
<option value="Room 16">Room 16</option>
<option value="Room 17">Room 17</option>
<option value="Room 18">Room 18</option>
<option value="Room 19">Room 19</option>
<option value="Room 20">Room 20</option>
<option value="Room 21">Room 21</option>
<option value="Room 22">Room 22</option>
<option value="Room 23">Room 23</option>
<option value="Room 24">Room 24</option>
<option value="Room 25">Room 25</option>
</select>
</div>
<div data-role="fieldcontain">
<select name="item" name="item" id="item" data-native-menu="false">
<option value="<?php
if(!isset($error['item'])) {
echo $item; } ?>" selected><?php if($_POST['item'] == "") {
echo "Item"; } else { echo $item; }?></option>
<option value="Iron">Iron</option>
<option value="Microwave">Microwave</option>
<option value="Kettle">Kettle</option>
<option value="TV">TV</option>
<option value="Clock Radio">Clock Radio</option>
<option value="Phone">Phone</option>
</select>
</div>
<div data-role="fieldcontain">
<select name="brand" name="brand" id="brand" data-native-menu="false">
<option value="<?php
if(!isset($error['brand'])) {
echo $brand; } ?>" selected><?php if($_POST['brand'] == "") {
echo "Brand"; } else { echo $brand; }?></option>
<option value="Iron KAMBROOK KI785">Iron - KAMBROOK KI785</option>
<option value="Microwave SAMSUNG BLACK">Microwave - SAMSUNG BLACK</option>
<option value="Kettle NERO EXPRESS BLACK">Kettle - NERO EXPRESS BLACK</option>
<option value="TV SAMSUNG 43"">TV - SAMSUNG 43"</option>
<option value="TV PHILIPS 40"">TV - PHILIPS 40"</option>
<option value="Clock Radio PHILIPS">Clock Radio - PHILIPS</option>
<option value="Clock Radio - IHOME">Clock Radio - IHOME</option>
<option value="Phone - BLACK TE">Phone - BLACK TEL</option>
<option value="OTHER">OTHER</option>
</select>
</div>
<div data-role="fieldcontain">
<select name="quality" name="quality" id="quality" data-native-menu="false">
<option value="<?php
if(!isset($error['quality'])) {
echo $quality; } ?>" selected><?php if($_POST['quality'] == "") {
echo "Quality"; } else { echo $quality; }?></option>
<option value="Poor">Poor</option>
<option value="Very Bad">Very Bad</option>
<option value="Bad">Bad</option>
<option value="Average">Average</option>
<option value="Good">Good</option>
<option value="Very Good">Very Good</option>
<option value="Excellent">Excellent</option>
</select>
</div>
<div class="ui-body ui-body-b">
<fieldset class="ui-grid-a">
<div class="ui-block-a"><input type="reset" id="reset" value="Reset" data-theme="d" value="Cancel"></div>
<div class="ui-block-b"><input type="submit" name="submit" id="submit" value="submit" data-theme="a" value="Submit"></div>
</fieldset>
</div>
</form>
</div>
</div>
</body>
</html>