The Timer control can work as a trigger to an area of the page that is wrapped with an UpdatePanel Control. It performs postbacks at defined intervals. The Interval property is defined in milliseconds, so that setting the Interval property to 5000 milliseconds will refresh the UpdatePanel control every 5 seconds.
The following asp.net program placed a Timer and label controls inside the UpdatePanel control area and one label control outside the UpdatePanel control area. When you run this program first label shows the current server time as page loaded time. After five seconds the second Label inside the UpdatePanel control shows the current server time. After that each five seconds you can see the second label only updating the current server time , because partal page updating is happening at defined intervals.
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