The SourceType property allows you to return and set the system type for the MsgObject or Event object.

Syntax for method invocation:

 SourceType : String

Example. When relay 1 closes (for example, the button connected to the relay is pressed), print the frames from cameras 1 and 2.

 if (Event.SourceType == "GRELE" && Event.SourceId == "1" && Event.Action == "ON")
{
  //activating the Camera 1 Surveillance window
  DoReactStr("MONITOR","1","ACTIVATE_CAM", "cam<1>");  
  //printing the frame from Camera 1
  DoReactStr("MONITOR","1","KEY_PRESSED","key<PRINT>");
  //activating the Camera 2 Surveillance window
  DoReactStr("MONITOR","1","ACTIVATE_CAM", "cam<2>");
  //printing the frame from Camera 2
  DoReactStr("MONITOR","1","KEY_PRESSED","key<PRINT>");
}