在普通的下，可以通过在页面上注明 validateRequest=“false" 这个选项来关闭请求对注入攻击的验证，但在mvc下则不行。而且，在 4.0下，哪怕是在 action 上注明 [validateInput(false)] 也无法让验证关闭。对此微软的解释是：
Request Validation
The request validation feature in provides a certain level of default protection against cross-site scripting (XSS) attacks. In previous versions of , request validation was enabled by default. However, it applied only to pages (.aspx files and their class files) and only when those pages were executing.
In 4, by default, request validation is enabled for all requests, because it is enabled before theBeginRequestphase of an HTTP request. As a result, request validation applies to requests for all resources, not just .aspx page requests. This includes requests such as Web service calls and custom HTTP handlers. Request validation is also active when custom HTTP modules are reading the contents of an HTTP request.
As a result, request validation errors might now occur for requests that previously did not trigger errors. To revert to the behavior of the 2.0 request validation feature, add the following setting in the Web.config file:
<httpRuntime requestValidationMode="2.0" />
However, we recommend that you analyze any request validation errors to determine whether existing handlers, modules, or other custom code accesses potentially unsafe HTTP inputs that could be XSS attack vectors.
4 Breaking Changes
