@OnNet

Overview

@OnNet() is a method decorator used to register a client-side network event handler.

Network events are sent from the server to the client using FiveM’s network event system (emitNet → onNet).

This decorator allows client controllers to react to those events declaratively, without manually calling onNet(...).

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Execution Model

• Events are initiated by the server
• Handlers run exclusively on the client
• The framework binds the handler during client bootstrap
• Arguments are passed exactly as emitted by the server

Client network events are reactive by nature.

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Decorator Signature

@OnNet(eventName)

Arguments

• eventName The name of the network event to listen to.

This name must match the event emitted by the server.

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Handler Signature

Client network handlers do not receive a Player parameter.

@OnNet('ui:setVisible')
setVisible(isVisible: boolean) {}

The handler parameters correspond directly to the arguments sent by the server.

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Argument Handling

• Arguments are received positionally
• No implicit validation is applied
• Payload shape must be agreed upon with the server

If validation or transformation is required, it should be handled inside the method body.

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Example

@Controller()
export class UiController {

  @OnNet('ui:setVisible')
  setVisible(isVisible: boolean) {
    // Update UI visibility
  }

  @OnNet('ui:updateData')
  updateData(data: { title: string; count: number }) {
    // React to server-driven state
  }
}

Server-side emission:

emitNet('ui:setVisible', playerId, true)
emitNet('ui:updateData', playerId, { title: 'Shop', count: 3 })

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Error Handling

• Handlers are automatically wrapped by the framework
• Exceptions are caught and logged
• Client runtime stability is preserved

Errors do not propagate back to the server.

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Lifecycle Considerations

• Events can be received at any time after client bootstrap
• There is no buffering guarantee
• If the client reconnects, missed events are lost

Client network events should be used for state updates, not critical logic.

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Relation to Server OnNet

Aspect	Server	Client
Initiator	Client	Server
Context	Player	None
Validation	Supported (Zod)	Manual
Security	Enforced by framework	N/A
Use case	Gameplay / authority	UI / feedback

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Notes

• This decorator binds to FiveM’s onNet(...) client API
• Intended for client-side controllers
• Arguments are delivered as-is
• Use @OnNet() for server-side network handlers

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Summary

@OnNet() provides:

• Declarative client-side event handling
• Clean separation from server logic
• Safe error isolation
• A clear reactive model

If the server needs to notify the client, this is the correct tool.