1. 有时候关闭webview子页面的时候会出错。一般是因为线程的问题

try

{

//有时候在并行编程中，通过ui主线程来处理并不能够奏效，这时候需要通过禁用UI线程，这样就不会出错：

var previous = UIApplication.CheckForIllegalCrossThreadCalls;

UIApplication.CheckForIllegalCrossThreadCalls = false;

mainWebView.ViewWithTag(99).RemoveFromSuperview();

UIApplication.CheckForIllegalCrossThreadCalls = previous;

}

catch (Exception ex)

{

//在主线程更新UI操作

InvokeOnMainThread(() => {

mainWebView.ViewWithTag(99).RemoveFromSuperview();

});

}

　　2. alert提示框

UIAlertView messageBox = new UIAlertView("提示", "你点击了一个按钮", null, "Close", "OK");                        messageBox.Clicked += (caller, buttonArgs) =>                        {                            Console.Write("qqqqqqqq");                                                    };                        messageBox.Show();