添加类
public class RequestValidatorDisabled:RequestValidator
{
    protected override bool IsValidRequestString(HttpContext context, string value, RequestValidationSource requestValidationSource, string collectionKey, out int validationFailureIndex)
    {
        validationFailureIndex = -1;
        return true;
    }
    public RequestValidatorDisabled()
    {
        //
        // TODO: 在此处添加构造函数逻辑
        //
    }
}
配置web.config
<system.web>
<httpRuntime requestValidationType="RequestValidatorDisabled"/>
<system.web>