COUNTDOWN-CLOCK.JS

Allows you to place a countdown to any future date of your choice on your website. The one on this page is programmed to display the time left for christmas. The format of the pareters year, month, day, hour, minute is yy, mm, dd, hh, mm. Feel free to modify the functions to your own liking. The script currently gets its current date from the client, a truer way of implementing a countdown to any particular date would be to somehow obtain it from the server.

COUNTDOWN-CLOCK.JS

function countdown(year, month, day, hour, minute, format, id)
         {
         Today = new Date();
         Todays_Year = Today.getFullYear() - 2000;
         Todays_Month = Today.getMonth();                  
         
         //Convert both today's date and the target date into miliseconds.                           
         Todays_Date = (new Date(Todays_Year, Todays_Month, Today.getDate(), 
                                 Today.getHours(), Today.getMinutes(), Today.getSeconds())).getTime();                                 
         Target_Date = (new Date(year, month - 1, day, hour, minute, 00)).getTime();                  
         
         //Find their difference, and convert that into seconds.                  
         Time_Left = Math.round((Target_Date - Todays_Date) / 1000);
         
         if(Time_Left < 0)
            Time_Left = 0;
         
         var innerHTML = '';
         
         switch(format)
               {
               case 0:
                    //The simplest way to display the time left.
                    innerHTML = Time_Left + ' seconds';
                    break;
               case 1:
                    //More datailed.
                    days = Math.floor(Time_Left / (60 * 60 * 24));
                    Time_Left %= (60 * 60 * 24);
                    hours = Math.floor(Time_Left / (60 * 60));
                    Time_Left %= (60 * 60);
                    minutes = Math.floor(Time_Left / 60);
                    Time_Left %= 60;
                    seconds = Time_Left;
                    
                    dps = 's'; hps = 's'; mps = 's'; sps = 's';
                    //ps is short for plural suffix.
                    if(days == 1) dps ='';
                    if(hours == 1) hps ='';
                    if(minutes == 1) mps ='';
                    if(seconds == 1) sps ='';
                    
                    innerHTML = days + ' day' + dps + ' ';
                    innerHTML += hours + ' hour' + hps + ' ';
                    innerHTML += minutes + ' minute' + mps + ' and ';
                    innerHTML += seconds + ' second' + sps;
                    break;
               default: 
                    innerHTML = Time_Left + ' seconds';
               }                   
                    
            document.getElementById(id).innerHTML = innerHTML;     
               
         //Recursive call, keeps the clock ticking.
         setTimeout('countdown(' + year + ',' + month + ',' + day + ',' + hour + ',' + minute + ',' + format + ', \'' + id + '\');', 1000);
         }