# cast.[framework](https://developers.google.com/cast/docs/reference/web_receiver/cast.framework).[system](https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.system).Message

class static

A custom message received from a sender. To listen for custom events use the
[cast.framework.CastReceiverContext#addCustomMessageListener](https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.CastReceiverContext#addCustomMessageListener) method.

## Constructor

### Message

new
Message(type, senderId, data)

| #### Parameter ||
|---|---|
| type | string The message type. It is always "message". |
| senderId | string The sender ID. |
| data | any type The message payload. Value must not be null. |

## Properties

### data

constant

non-null any type

The message payload.

### senderId

constant

string

The sender ID.

### type

<br />

The message type. It is always "message".