MessageEvent.md

MessageEvent

Namespace: SpawnDev.SpawnJS.JSObjects
Inherits: MessageEvent
Source: JSObjects/MessageEvent.cs
MDN Reference: MessageEvent on MDN

The MessageEvent interface represents a message received by a target object. https://developer.mozilla.org/en-US/docs/Web/API/MessageEvent

Constructors

Signature	Description
MessageEvent(SpawnJSObjectReference _ref)	Deserialization constructor
MessageEvent(SpawnJSObjectReference _ref)	Deserialization constructor

Properties

Property	Type	Access	Description
Data	TData	get	Message data as type TData
TypeOfData	string?	get	non-standard method returns the typeof this.data returns "String", "Blob", or "ArrayBuffer" (could also return "Object", "Boolean", "Number", other?)
Origin	string	get	A string representing the origin of the message emitter.
LastEventId	string	get	A string representing a unique ID for the event.
Ports	Array<MessagePort>	get	An array of MessagePort objects representing the ports associated with the channel the message is being sent through (where appropriate, e.g. in channel messaging or when sending a message to a shared worker).

Methods

Method	Return Type	Description
GetData()	T	The data sent by the message emitter. (data property with TValue typed get accessor) Type to get property as
GetSource()	T	A MessageEventSource (which can be a WindowProxy, MessagePort, or ServiceWorker object) representing the message emitter. (source property with TValue typed get accessor) Type to get property as

Examples

SpawnDev.SpawnJS Mapping Note: The JavaScript examples below show the standard Web API usage. In SpawnDev.SpawnJS, the same API is available with C# conventions:

• Properties and methods use PascalCase (e.g., readyState becomes ReadyState)
• Events use ActionEvent with +=/-= (e.g., addEventListener("click", fn) becomes OnClick += handler)
• Async methods return Task<T> instead of Promise<T>
• Objects should be disposed with using statements
• Access via JS.Get<MessageEvent>(...) or constructor new MessageEvent(...)

const myWorker = new SharedWorker("worker.js");

myWorker.port.start();

[first, second].forEach((input) => {
  input.onchange = () => {
    myWorker.port.postMessage([first.value, second.value]);
    console.log("Message posted to worker");
  };
});

myWorker.port.onmessage = (e) => {
  result1.textContent = e.data;
  console.log("Message received from worker");
};

See full example on MDN