Insert image pada PHP PDO

saya ingin memasukkan gambar pada php dengan metode pdo. saya memiliki 3 file, dt_mhs.php untuk menampilkan data, data_baru.php untuk form upload, dan data.inc.php untuk proses upload.

tapi saya bingung gimana caranya upload foto, karena saya baru kali ini menggunakan metode PDO.

berikut ini source code pada file data.inc.php :

<?php
class Mhs{

	private $conn;
	private $table_name = "wp_data";

	public $id;
	public $ni;
	public $nm;
	public $jk;
	public $tl;
	public $gl;
	public $ls;
	public $jr;
	public $jj;
	public $sm;
	public $ft;

	public function __construct($db){
		$this->conn = $db;
	}

	function insert(){

		$query = "insert into ".$this->table_name." values('','$_POST[ni]','$_POST[nm]','$_POST[jk]','$_POST[tl]','$_POST[gl]','$_POST[ls]','$_POST[jr]','$_POST[jj]','$_POST[sm]','$_POST[ft]')";
		$stmt = $this->conn->prepare($query);
		$stmt->bindParam(1, $this->ni);
		$stmt->bindParam(2, $this->nm);
		$stmt->bindParam(3, $this->jk);
		$stmt->bindParam(4, $this->tl);
		$stmt->bindParam(5, $this->gl);
		$stmt->bindParam(6, $this->ls);
		$stmt->bindParam(7, $this->jr);
		$stmt->bindParam(8, $this->jj);
		$stmt->bindParam(9, $this->sm);
		$stmt->bindParam(10, $this->ft);

		if($stmt->execute()){
			return true;
		}else{
			return false;
		}

	}

	function readAll(){

		$query = "SELECT * FROM ".$this->table_name." ORDER BY id_data";
		$stmt = $this->conn->prepare( $query );
		$stmt->execute();

		return $stmt;
	}
	function countAll(){

		$query = "SELECT * FROM ".$this->table_name." ORDER BY id_data ASC";
		$stmt = $this->conn->prepare( $query );
		$stmt->execute();

		return $stmt->rowCount();
	}

	function readOne(){

		$query = "SELECT * FROM " . $this->table_name . " WHERE id_data=? LIMIT 0,1";

		$stmt = $this->conn->prepare( $query );
		$stmt->bindParam(1, $this->id);
		$stmt->execute();

		$row = $stmt->fetch(PDO::FETCH_ASSOC);

		$this->id = $row['id_data'];
		$this->ni=$row['nim'];
		$this->nm=$row['nama'];
		$this->jk=$row['jenis'];
		$this->tl=$row['tempat_lahir'];
		$this->gl=$row['tgl_lahir'];
		$this->ls=$row['alamat_skrg'];
		$this->jr=$row['jurusan'];
		$this->jj=$row['jenjang'];
		$this->sm=$row['semester'];
		$this->ft=$row['foto'];

	}

	// update the product
	function update(){

		$query = "UPDATE
					" . $this->table_name . "
				SET
					nim = :ni
					nama = :nm
					jenis = :jk
					tempat_lahir = :tl
					tgl_lahir = :gl
					alamat_skrg = :ls
					jurusan = :jr
					jenjang = :jj
					semester = :sm
					foto = :ft

				WHERE
					id_data=:id";

		$stmt = $this->conn->prepare($query);

		$stmt->bindParam(':ni', $this->ni);
		$stmt->bindParam(':nm', $this->nm);
		$stmt->bindParam(':jk', $this->jk);
		$stmt->bindParam(':tl', $this->tl);
		$stmt->bindParam(':gl', $this->gl);
		$stmt->bindParam(':ls', $this->ls);
		$stmt->bindParam(':jr', $this->jr);
		$stmt->bindParam(':jj', $this->jj);
		$stmt->bindParam(':sm', $this->sm);
		$stmt->bindParam(':ft', $this->ft);
		$stmt->bindParam(':id', $this->id);

		// execute the query
		if($stmt->execute()){
			return true;
		}else{
			return false;
		}
	}

	// delete the product
	function delete(){

		$query = "DELETE FROM " . $this->table_name . " WHERE id_data = ?";

		$stmt = $this->conn->prepare($query);
		$stmt->bindParam(1, $this->id);

		if($result = $stmt->execute()){
			return true;
		}else{
			return false;
		}
	}
	function hapusell($ax){

		$query = "DELETE FROM " . $this->table_name . " WHERE id_data in $ax";

		$stmt = $this->conn->prepare($query);

		if($result = $stmt->execute()){
			return true;
		}else{
			return false;
		}
	}
}
?>

berikut inisource code data_baru.php

 <?php
include_once 'header.php';
if($_POST){

	include_once 'includes/data.inc.php';

	$eks = new Mhs($db);

	$eks->ni= $_POST['ni'];
	$eks->nm= $_POST['nm'];
	$eks->jk= $_POST['jk'];
	$eks->tl= $_POST['tl'];
	$eks->gl= $_POST['gl'];
	$eks->ls= $_POST['ls'];
	$eks->jr= $_POST['jr'];
	$eks->jj= $_POST['jj'];
	$eks->sm= $_POST['sm'];

	if($eks->insert()){
?>
<script type="text/javascript">
window.onload=function(){
	showStickySuccessToast();
};
</script>
<?php
	}

	else{
?>
<script type="text/javascript">
window.onload=function(){
	showStickyErrorToast();
};
</script>
<?php
	}
}
?>
		<div class="row">
		  <div class="col-xs-12 col-sm-12 col-md-2">
		  </div>
		  <div class="col-xs-12 col-sm-12 col-md-8">
		  	<div class="panel panel-default">
		<div class="panel-body">
		  	<div class="row">
				<div class="col-md-6 text-left">
		  			<h3>Tambah Nilai Preferensi</h3>
		  		</div>
		  		<div class="col-md-6 text-right">
		  			<h3>
		  				<button type="button" onclick="location.href='dt_mhs.php'" class="btn btn-success">Kembali</button>
		  			</h3>
		  		</div>
		  	</div>

			    <form method="post">
				<div class="form-group">
				    <label for="ni">NIM</label>
				    <input type="text" class="form-control" id="ni" name="ni" required>
				  </div>
				  <div class="form-group">
				    <label for="nm">Nama Lengkap</label>
				    <input type="text" class="form-control" id="nm" name="nm" required>
				  </div>
				  <div class="form-group">
				    <label for="jk">Jenis Kelamin</label>
				    <select class="form-control" id="jk" name="jk">
				    	<option value='Laki-laki'>Laki-laki</option>
				    	<option value='Perempuan'>Perempuan</option>
				    </select>
				  </div>
				  <div class="form-group">
				    <label for="tl">Tempat Lahir</label>
				    <input type="text" class="form-control" id="tl" name="tl" required>
				  </div>
				  <div class="form-group">
				    <label for="gl">Tanggal Lahir</label>
				    <input type="date" class="form-control" id="gl" name="gl" required>
				  </div>
				  <div class="form-group">
				    <label for="ls">Alamat Sekarang</label>
				    <input type="text" class="form-control" id="ls" name="ls" required>
				  </div>
				  <div class="form-group">
				    <label for="jr">Jurusan</label>
				    <input type="text" class="form-control" id="jr" name="jr" required>
				  </div>
					<div class="form-group">
				    <label for="jj">Jenjang</label>
				    <select class="form-control" id="jj" name="jj">
				    	<option value='D1'>D1</option>
				    	<option value='D2'>D2</option>
						<option value='D3'>D3</option>
				    	<option value='D4'>D4</option>
						<option value='S1'>S1</option>
				    	<option value='S2'>S2</option>
				    </select>
				  </div>
				  <div class="form-group">
				    <label for="sm">Semester</label>
				    <input type="text" class="form-control" id="sm" name="sm" required>
				  </div>
				  <div class="form-group ">
					<label for="ft">Unggah Foto Diri</label>
                <input class="btn btn-default" type="file" required="required" name="ft" id="ft" enctype="multipart/form-data" accept=""/image"/>
                <span class="help-block"></span>
            </div>
				  <button type="submit" class="btn btn-primary" name="btn-add">Simpan</button>
				</form>
				</div>
				</div>

		  </div>
		  <div class="col-xs-12 col-sm-12 col-md-2">
		  </div>
		</div>
		<?php
include_once 'footer.php';
?>

mohon bantuaannya.. terima kasih..