Tham khảo sách 'beginning ajax with php ( php and ajax tool tips one of the more) - ', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 9 27 06 2 49 PM Page 44 44 CHAPTER 3 PHP AND AJAX Tool Tips One of the more common DHTML tricks you will see on the Internet is the tool tip. This is basically a little box filled with information that will appear above a properly placed cursor. While this is all fine and dandy the information contained within said box in non-Ajax enabled web sites is usually either hard-coded in or potentially loaded through some serverside trickery. What you will do in the next example is load the box dynamically using Ajax. As a useful addition to your calendar application it would be nice to dynamically display a box with all currently assigned tasks when a user hovers over a certain date. The PHP script would henceforth have to scour the database and return any instances of tasks associated with said day. Since I m not going to get into databases just yet I ll have you build the script to accommodate an array of tasks for now just to showcase the tool tip functionality. First off let s have a look at the file in order to view the changes to the calendar code Let s make an appropriate number of rows. for k 1 k numrows k tr php Use 7 columns for 7 days . for i 0 i 7 i startdate if startdate 0 startdate lastday If we have a blank day in the calendar. td style background FFFFFF nbsp td php else if startdate date j month date n year date Y td onclick createform event class calendartodayoff onmouseover calendartodayover checkfortasks php echo year . - . month . - . startdate event onmouseout calendartodayoff hidetask php echo date j td php else td onclick createform event class calendaroff onmouseover calendarover checkfortasks php echo year . - . month . - . startdate event onmouseout calendaroff hidetask php echo startdate td php tr php 9 27 06 2 49 PM Page 45 CHAPTER 3 PHP AND AJAX 45 The major change made here is calling a checkfortasks function that is fired by the onmouseover .
