In addition to reading server tag values, HTML HMI provides several mechanisms for allowing users to input and set server values. By applying configurations to an HTML element, you can quickly create:
  • Toggle Buttons
    Alternate between boolean states with a click or other client-side event
  • Input Dialogs
    Display confugurable modal dialogs to accept user input
  • Confirmation
    Require user confirmation before changing server values to prevent accidental updates
Also, HTML HMI exposes a programmatic interface for Javascript developers to read and write server values within their own code.
Toggle Button
CLICK ME
Display Value
True
Confirmation
CLICK ME
User Input
SET VALUE

<!-- 
The oas-tag-set attribute makes the element interactive.

The 'tag' setting picks the server tag to alter.
The 'evt' setting monitors the click event.
The 'set' setting tells the server to toggle the value between true and false.
-->
<div id="imgPump1"
  oas-tag-set='{"tag":"Pump.Value",
    "config":{
      "evt":"click",
      "set":"toggle"}
    }' >
CLICK ME
</div>
      

/*
You also have the option to programmatically read and write server values within your own client-side javascript code.
*/

// Read the Pump.Value server tag and assign to a variable
var pv = OPC.get_value("Pump.Value");

// Set the server value of Pump.Value to "True"
OPC.set_value("Pump.Value","True");