winform窗体应用程序，实现功能为当窗体加载时，弹出对话框，询问是否查看窗体，如果单击是按钮，则查看窗体。当关闭窗体时，弹出提示框，询问是否关闭当前窗体，如果单击是按钮，则关闭窗体。-winform application form, to achieve the function of when the form is loaded, a dialog box asking if you view the form, if you click a button, and then vie