public class XSS
  {
    private HtmlSanitizer sanitizer;
    public XSS()
    {
      sanitizer = new HtmlSanitizer();
      //sanitizer.AllowedTags.Add("div");//标签白名单
      sanitizer.AllowedAttributes.Add("class");//标签属性白名单,默认没有class标签属性      
      //sanitizer.AllowedCssProperties.Add("font-family");//CSS属性白名单
    }

    /// <summary>
    /// XSS过滤
    /// </summary>
    /// <param name="html">html代码</param>
    /// <returns>过滤结果</returns>
    public string Filter(string html)
    {
      string str = sanitizer.Sanitize(html);
      return str;
    }
  }

 public class FieldFilterAttribute : Attribute,IActionFilter
  {
    private XSS xss;
    public FieldFilterAttribute()
    {
      xss = new XSS();
    }

    //在Action方法之回之后调用
    public void OnActionExecuted(ActionExecutedContext context)
    {

    }

    //在调用Action方法之前调用
    public void OnActionExecuting(ActionExecutingContext context)
    {
      //获取Action参数集合
      var ps = context.ActionDescriptor.Parameters;
      //遍历参数集合
      foreach (var p in ps)
      {
        if (context.ActionArguments[p.Name] != null)
        {
          //当参数等于字符串
          if (p.ParameterType.Equals(typeof(string)))
          {
            context.ActionArguments[p.Name] = xss.Filter(context.ActionArguments[p.Name].ToString());
          }
          else if (p.ParameterType.IsClass)//当参数等于类
          {
            ModelFieldFilter(p.Name, p.ParameterType, context.ActionArguments[p.Name]);
          }
        }          

      }
    }

    /// <summary>
    /// 遍历修改类的字符串属性
    /// </summary>
    /// <param name="key">类名</param>
    /// <param name="t">数据类型</param>
    /// <param name="obj">对象</param>
    /// <returns></returns>
    private object ModelFieldFilter(string key, Type t, object obj)
    {
      //获取类的属性集合
      var ats = t.GetCustomAttributes(typeof(FieldFilterAttribute), false);


      if (obj != null)
      {
        //获取类的属性集合
        var pps = t.GetProperties();

        foreach (var pp in pps)
        {
          if(pp.GetValue(obj) != null)
          {
            //当属性等于字符串
            if (pp.PropertyType.Equals(typeof(string)))
            {
              string value = pp.GetValue(obj).ToString();
              pp.SetValue(obj, xss.Filter(value));
            }
            else if (pp.PropertyType.IsClass)//当属性等于类进行递归
            {
              pp.SetValue(obj, ModelFieldFilter(pp.Name, pp.PropertyType, pp.GetValue(obj)));
            }
          }
          
        }
      }

      return obj;
    }
  }

  //属性过滤器
  [FieldFilter]
  public class NoteBookController : ManageController
  {
    //笔记操作接口
    private INoteBookAppService _noteBookApp;
    public NoteBookController(INoteBookAppService noteBookApp)
    {
      this._noteBookApp = noteBookApp;
    }
    public IActionResult Tab()
    {
      return View();
    }

  }