Interface MessagePort
onmessage: (this: MessagePort, ev: MessageEvent) => any;
onmessageerror: (this: MessagePort, ev: MessageEvent) => any;
addEventListener<K extends keyof MessagePortEventMap>(
type: K,
listener: (this: MessagePort, ev: MessagePortEventMap[K]) => any,
options?: boolean | AddEventListenerOptions,
): void;
addEventListener(
type: string,
listener: EventListenerOrEventListenerObject,
options?: boolean | AddEventListenerOptions,
): void;
close(): void;
dispatchEvent(event: Event): boolean;
postMessage(message: any, transfer: Transferable[]): void;
postMessage(message: any, options?: StructuredSerializeOptions): void;
removeEventListener<K extends keyof MessagePortEventMap>(
type: K,
listener: (this: MessagePort, ev: MessagePortEventMap[K]) => any,
options?: boolean | EventListenerOptions,
): void;
removeEventListener(
type: string,
listener: EventListenerOrEventListenerObject,
options?: boolean | EventListenerOptions,
): void;
start(): void;
}
                 
                    
                  Hierarchy
              
              - EventTarget- MessagePort (View Summary)
 
 Index
Properties
Methods
 Methods
addEventListener  
- addEventListener<K extends keyof MessagePortEventMap>(
 type: K,
 listener: (this: MessagePort, ev: MessagePortEventMap[K]) => any,
 options?: boolean | AddEventListenerOptions,
 ): void
- Appends an event listener for events whose type attribute value is type. The callback argument sets the callback that will be invoked when the event is dispatched. - The options argument sets listener-specific options. For compatibility this can be a boolean, in which case the method behaves exactly as if the value was specified as options's capture. - When set to true, options's capture prevents callback from being invoked when the event's eventPhase attribute value is BUBBLING_PHASE. When false (or not present), callback will not be invoked when event's eventPhase attribute value is CAPTURING_PHASE. Either way, callback will be invoked if event's eventPhase attribute value is AT_TARGET. - When set to true, options's passive indicates that the callback will not cancel the event by invoking preventDefault(). This is used to enable performance optimizations described in § 2.8 Observing event listeners. - When set to true, options's once indicates that the callback will only be invoked once after which the event listener will be removed. - If an AbortSignal is passed for options's signal, then the event listener will be removed when signal is aborted. - The event listener is appended to target's event listener list and is not appended if it has the same type, callback, and capture. - Type Parameters- K extends keyof MessagePortEventMap
 - Parameters- type: K
- listener: (this: MessagePort, ev: MessagePortEventMap[K]) => any
- Optionaloptions: boolean | AddEventListenerOptions
 - Returns void
- addEventListener(
 type: string,
 listener: EventListenerOrEventListenerObject,
 options?: boolean | AddEventListenerOptions,
 ): void
- Appends an event listener for events whose type attribute value is type. The callback argument sets the callback that will be invoked when the event is dispatched. - The options argument sets listener-specific options. For compatibility this can be a boolean, in which case the method behaves exactly as if the value was specified as options's capture. - When set to true, options's capture prevents callback from being invoked when the event's eventPhase attribute value is BUBBLING_PHASE. When false (or not present), callback will not be invoked when event's eventPhase attribute value is CAPTURING_PHASE. Either way, callback will be invoked if event's eventPhase attribute value is AT_TARGET. - When set to true, options's passive indicates that the callback will not cancel the event by invoking preventDefault(). This is used to enable performance optimizations described in § 2.8 Observing event listeners. - When set to true, options's once indicates that the callback will only be invoked once after which the event listener will be removed. - If an AbortSignal is passed for options's signal, then the event listener will be removed when signal is aborted. - The event listener is appended to target's event listener list and is not appended if it has the same type, callback, and capture. - Parameters- type: string
- listener: EventListenerOrEventListenerObject
- Optionaloptions: boolean | AddEventListenerOptions
 - Returns void
close
dispatchEvent 
postMessage 
- postMessage(message: any, transfer: Transferable[]): void
- Posts a message through the channel. Objects listed in transfer are transferred, not just cloned, meaning that they are no longer usable on the sending side. - Throws a "DataCloneError" DOMException if transfer contains duplicate objects or port, or if message could not be cloned. - Parameters- message: any
- transfer: Transferable[]
 - Returns void
- postMessage(message: any, options?: StructuredSerializeOptions): void
- Parameters- message: any
- Optionaloptions: StructuredSerializeOptions
 - Returns void
removeEventListener  
- removeEventListener<K extends keyof MessagePortEventMap>(
 type: K,
 listener: (this: MessagePort, ev: MessagePortEventMap[K]) => any,
 options?: boolean | EventListenerOptions,
 ): void
- Removes the event listener in target's event listener list with the same type, callback, and options. - Type Parameters- K extends keyof MessagePortEventMap
 - Parameters- type: K
- listener: (this: MessagePort, ev: MessagePortEventMap[K]) => any
- Optionaloptions: boolean | EventListenerOptions
 - Returns void
- removeEventListener(
 type: string,
 listener: EventListenerOrEventListenerObject,
 options?: boolean | EventListenerOptions,
 ): void
- Removes the event listener in target's event listener list with the same type, callback, and options. - Parameters- type: string
- listener: EventListenerOrEventListenerObject
- Optionaloptions: boolean | EventListenerOptions
 - Returns void
This Channel Messaging API interface represents one of the two ports of a MessageChannel, allowing messages to be sent from one port and listening out for them arriving at the other.
MDN Reference