From Xojo Documentation
The Timer executes some code once or repeatedly after a period of time has passed.
Timer is covered in more detail in the UserGuide:Timers topic.
The Web Timer is very similar to the standard Timer control. The important difference is that the Web Timer can be server-side or client side meaning that it would be part of the webpage it's on.
A Web Timer can be used to update controls on the page, for example. A standard Timer control will only execute server-side, so it cannot contact the client.
Run - The Run event is called when the Timer period is reached.
RunMode - Indicates if the Timer is Off, Single or Multiple.
Period - The number of milliseconds between calls to the Action event.
Reset - Call this to reset and restart the Timer.
The Web Timer provides the same functionality as the Desktop Timer control. This example updates the value on a label (SecondsPassedLabel) on the web page using the WebTimer. This code in the WebTimer updates the label:
You can also add a button to start and stop the timer. This code is in a Button's Pressed event:
Timer1.Mode = WebTimer.RunModes.Multiple
Me.Caption = "Stop" // button caption
SecondsPassedLabel.Value = "0"
Timer1.Mode = WebTimer.RunModes.Off // Turn off the timer
Me.Caption = "Start"
These project demonstrate ways that a Web Timer is used to update the UI: