EventsEmit cannot handle file types, Can you add a file type

[zundaren]

Is your feature request related to a problem? Please describe.

js generates a drag file event "DragEvent", e.dataTransfer.items or Blob，carry out EventsEmit("file", data), golang print [map[]]

Describe the solution you'd like

runtime.EventsOn(ctx, "file", func(optionalData ...interface{}) {
 // hope to optionalData.(*multipart.FileHeader)
  fmt.Println(optionalData.(*multipart.FileHeader))
})

Describe alternatives you've considered

No response

Additional context

No response