使用Selector swift传递值

class MyUIBarButtonItem : UIBarButtonItem {
    var emailAddr = String()
}

let btnEmail = MyUIBarButtonItem.init(title: "Email Me", style: .plain, target: self, action: #selector(onSendEmail as (String) -> ()))
btnEmail.emailAddr = "some@email.com"


func onSendEmail(_ sender: Any){
    let btn = sender as! MyUIBarButtonItem
    print(btn.emailAddr)
}