如果您需要在表单上接受原始HTML，则必须将page指令的ValidateRequest属性设置为false.请注意，尽管这样做将允许所有HTML，包括任何人都想到的讨厌的东西，都可以从该页面上载.您应谨慎使用

If you need to accept raw HTML on your form you must set the ValidateRequest property of the page directive to false. Be warned though this will allow all HTML, including anything nasty anyone can think of, to be uploaded from that page. You should use it with caution