ปัญหาลบแถวที่สร้างด้วย jquery ไม่ได้ กดปุ่มลบแล้วมันไม่ทำงานเหมือนที่สร้างไว้อยู่แล้ว

$(document).ready(function(){
		//addrow
		$('#addrow').click(function(){
			var tr = $('<tr class="tr"></tr>');
			var td1 = $('<td><input name="supjectID" type="text" class="supjectID" size="11" maxlength="11" /></td>');
			var td2 = $('<td><input name="supjectName" type="text" class="supjectName" size="30" maxlength="30" /></td>');
			var td3 = $('<td><input name="supjectCredit" type="text" class="supjectCredit" size="10" maxlength="10" /></td>');
			var td4 = $('<td><input name="day" type="text" class="day" size="8" maxlength="8" /></td>');
			var td5 = $('<td><input name="timebegin" type="text" class="timebegin" size="10" maxlength="10" /></td>');
			var td6 = $('<td><input name="timeend" type="text" class="timeend" size="10" maxlength="10" /></td>');
			var td7 = $('<td><input name="room" type="text" class="room" size="10" maxlength="10" /></td>');
			var td8 = $('<td align="center"><img class="deleterow" src="images/delete.png" width="20" height="20" /></td>');
			
			tr.append(td1);
			tr.append(td2);
			tr.append(td3);
			tr.append(td4);
			tr.append(td5);
			tr.append(td6);
			tr.append(td7);
			tr.append(td8);
			
			$('#taughttable').append(tr);
		});
		
		//deleterow
		 $('.deleterow').click(function(){
        $(this).parents('.tr').addClass('select');
        if (confirm('delete?')){           
            $(this).parents('.tr').remove();
        }else{
            $(this).parents('.tr').removeClass('select');
        }
    });

<tr class="tr">
    <td><input name="supjectID" type="text" class="supjectID" size="11" maxlength="11" /></td>
    <td><input name="supjectName" type="text" class="supjectName" size="30" maxlength="30" /></td>
    <td><input name="supjectCredit" type="text" class="supjectCredit" size="10" maxlength="10" /></td>
    <td><input name="day" type="text" class="day" size="8" maxlength="8"></td>
    <td><input name="timebegin" type="text" class="timebegin" size="10" maxlength="10" /></td>
    <td><input name="timeend" type="text" class="timeend" size="10" maxlength="10" /></td>
    <td><input name="room" type="text" class="room" size="10" maxlength="10" /></td>
    <td align="center"><img class="deleterow" src="images/delete.png" width="20" height="20" /></td>
  </tr>