Countdown timer in asp.net

问题:

I am using asp.net 3.5 with C#. I want to create a countdown timer and my requirement is like this:

Countdown end date: June 16 2010 So, till June 16 comes my timer will show the remeaning time.

Please let me know how to achieve it, I google it but i didn't get the excat solution to my problem.

Thanks in advance.

回答1:

This is something you need to solve with Javascript. The only thing you need to do from the server is set the end date as a Javascript variable. You need Javascript because you only load the page from the server. Afterwards you need to handle the countdown on the client.

Javascript

<script type="text/javascript">
    function countdown_clock(clockID, year, month, day, hour, minute) {
        countdown(clockID, year, month, day, hour, minute);
    }

    function countdown(clockID, year, month, day, hour, minute) {
        Today = new Date();
        Todays_Year = Today.getFullYear();
        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;

        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 = '';

        var clock = document.getElementById(clockID);
        clock.innerHTML = days + ' day' + dps + ' ';
        clock.innerHTML += hours + ' hour' + hps + ' ';
        clock.innerHTML += minutes + ' minute' + mps + ' and ';
        clock.innerHTML += seconds + ' second' + sps;

        //Recursive call, keeps the clock ticking.
        setTimeout('countdown("' + clockID + '",' + year + ',' + month + ',' + day + ',' + hour + ',' + minute + ');', 1000);
    }
</script>

ASP.NET

protected override void OnPreRender(EventArgs e)
    {
        DateTime endDate = new DateTime(2010, 6, 1, 0, 0, 0);
        string script = string.Format("countdown_clock('clock', {0}, {1}, {2}, {3}, {4});", endDate.Year, endDate.Month, endDate.Day, endDate.Hour, endDate.Minute);
        ScriptManager.RegisterStartupScript(this, this.GetType(), "countdown", script, true);

        base.OnPreRender(e);
    }

Script taken an modified for example purpose from My Little Scripts.

回答2:

If you like it easy, use DateTime.

DateTime EventTime = new DateTime(2010, 6, 16);
TimeSpan Duration = EventTime - DateTime.Now;
string TimeTillEvent = Duration.ToString();