Function runtime_event

runtime_event(
    params: {
        handler: CEventHandler;
        request: string;
        target?: EventTarget;
        type: string;
    },
): void
Adds or removes an event handler to the JavaScript runtime or individual element.
Parameters
- params: { handler: CEventHandler; request: string; target?: EventTarget; type: string }
  The named parameters.
  - handler: CEventHandler
    
    The handler called when the identified event is triggered or being removed.
  - request: string
    
    The request to carry out.
  - Optionaltarget?: EventTarget
    
    The element to attach an event handler to if it supports it.
  - type: string
    
    The event handler identifier.
Returns void
Example
```
// Listen for browser messages.
let message_handler = (evt) => {
  // Does something
};
runtime_event({
  request: EVENT_REQUEST.Add,
  type: "message",
  handler: message_handler,
});

// Then on app cleanup, remove the listener
runtime_event({
  request: EVENT_REQUEST.Remove,
  type: "message",
  handler: message_handler,
});
```
- Defined in codemelted.js:3862