ASP.NET MVC使用Action过滤器处理方法

古城微笑少年丶 2021-09-17 03:01 302阅读 0赞

Action过滤器在动作方法之前及之后运行，Result过滤器在动作结果被执行之前和之后运行。

**1、Action过滤器**

在ASP.NET MVC中创建MvcApp项目，创建文件夹Filter，然后新建类MyActionFilterAttribute（为了遵循默认的约定，名称以Attribute结尾），继承自ActionFilterAttribute类。ActionFilterAttribute类有如下4个方法。

using System;
     
    namespace System.Web.Mvc
    {
        [AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, Inherited = true, AllowMultiple = false)]
        public abstract class ActionFilterAttribute : FilterAttribute, IActionFilter, IResultFilter
        {
     
            protected ActionFilterAttribute();
     
            public virtual void OnActionExecuted(ActionExecutedContext filterContext);
     
            public virtual void OnActionExecuting(ActionExecutingContext filterContext);
     
            public virtual void OnResultExecuted(ResultExecutedContext filterContext);
     
            public virtual void OnResultExecuting(ResultExecutingContext filterContext);
        }
    }

实现MyActionFilterAttribute类：

using System;
 using System.Web.Mvc;
 
 namespace MvcApp.Filter
 {
 public class MyActionFilterAttribute : ActionFilterAttribute
 {
 public override void OnActionExecuting(ActionExecutingContext filterContext)
 {
 //1、获取请求的类名和方法名
 string strController = filterContext.RouteData.Values["controller"].ToString();
 string strAction = filterContext.RouteData.Values["action"].ToString();
 
 //2、用另一种方式获取请求的类名和方法名
 string strController2 = filterContext.ActionDescriptor.ControllerDescriptor.ControllerName;
 string strAction2 = filterContext.ActionDescriptor.ActionName;
 
 filterContext.HttpContext.Response.Write("控制器：" + strController + " ");
 filterContext.HttpContext.Response.Write("控制器：" + strController2 + " ");
 filterContext.HttpContext.Response.Write("Action：" + strAction + " ");
 filterContext.HttpContext.Response.Write("Action：" + strAction2 + " ");
 
 filterContext.HttpContext.Response.Write("Action执行前：" + DateTime.Now.ToString("yyyy-MM-dd hh:mm:ss fff") + " ");
 base.OnActionExecuting(filterContext);
 }
 
 public override void OnActionExecuted(ActionExecutedContext filterContext)
 {
 filterContext.HttpContext.Response.Write("Action执行后：" + DateTime.Now.ToString("yyyy-MM-dd hh:mm:ss fff") + " ");
 base.OnActionExecuted(filterContext);
 }
 }
 }

对于过滤器，我们可以把它们加在3个地方，一个是控制器上面（控制器下面的所有Action），一个是Action上面（指定标识的Action），另一个就是全局位置（所有控制器中的Action）。这里只演示在Action上面和Home控制器中：

[MyActionFilter]
    public ActionResult Index()
    {
        return View();
    }

**2、Result过滤器**

新建MyResultFilterAttribute类，继承ActionFilterAttribute：

using System;
 using System.Web.Mvc;
 
 namespace MvcApp.Filter
 {
 public class MyResultFilterAttribute : ActionFilterAttribute
 {
 /// <summary>
 /// 加载“视图”前执行
 /// </summary>
 /// <param name="filterContext"></param>
 public override void OnResultExecuting(ResultExecutingContext filterContext)
 {
 filterContext.HttpContext.Response.Write("加载视图前执行 OnResultExecuting" + DateTime.Now.ToString("yyyy-MM-dd hh:mm:ss fff") + " ");
 base.OnResultExecuting(filterContext);
 }
 
 /// <summary>
 /// 加载“视图”后执行
 /// </summary>
 /// <param name="filterContext"></param>
 public override void OnResultExecuted(ResultExecutedContext filterContext)
 {
 filterContext.HttpContext.Response.Write("加载视图后执行 OnResultExecuted" + DateTime.Now.ToString("yyyy-MM-dd hh:mm:ss fff") + " ");
 base.OnResultExecuted(filterContext);
 }
 }
 }

这里把MyResultFilter过滤器加在控制器上面，相当于给Home控制器中的所有的Action方法添加了MyResultFilter过滤器。

using MvcApp.Filter;
    using System.Web.Mvc;
     
    namespace MvcApp.Controllers
    {
        [MyResultFilter]
        public class HomeController : Controller
        {
            [MyActionFilter]
            public ActionResult Index()
            {
                return View();
            }
        }
    }

运行结果，如下图：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3Bhbl9qdW5iaWFv_size_16_color_FFFFFF_t_70][]

**示例：使用Action过滤器，实现操作日志的记录功能。**

在Models目录下创建OperateLogModel.cs（操作日志实体类）：

using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Web;
 
 namespace MvcApp.Models
 {
 /// <summary>
 /// 操作日志实体类
 /// </summary>
 public class OperateLogModel
 {
 /// <summary>
 /// 控制器名称
 /// </summary>
 public string ControllerName { get; set; }
 
 /// <summary>
 /// Action名称
 /// </summary>
 public string ActionName { get; set; }
 
 /// <summary>
 /// 功能模块
 /// </summary>
 public string FunctionalModule { get; set; }
 
 /// <summary>
 /// 操作类型
 /// </summary>
 public string OperationType { get; set; }
 
 /// <summary>
 /// 操作时间
 /// </summary>
 public DateTime OperationDate { get; set; }
 
 /// <summary>
 /// 路径
 /// </summary>
 public string Path { get; set; }
 
 /// <summary>
 /// 请求参数
 /// </summary>
 public string Params { get; set; }
 }
 }

创建Filter目录，并在该目录下创建OperateLogAttribute类，继承ActionFilterAttribute类：

using MvcApp.Models;
 using Newtonsoft.Json;
 using System;
 using System.IO;
 using System.Text;
 using System.Web;
 using System.Web.Mvc;
 
 namespace MvcApp.Filter
 {
 /// <summary>
 /// 操作日志
 /// </summary>
 public class OperateLogAttribute : ActionFilterAttribute
 {
 /// <summary>
 /// 功能模块
 /// </summary>
 public string FunctionalModule { get; set; }
 
 /// <summary>
 /// 操作类型
 /// </summary>
 public string OperationType { get; set; }
 
 /// <summary>
 /// 记录请求日志
 /// </summary>
 public override void OnActionExecuting(ActionExecutingContext filterContext)
 {
 //创建操作日志实体类
 OperateLogModel requestLog = new OperateLogModel();
 requestLog.ControllerName = filterContext.ActionDescriptor.ControllerDescriptor.ControllerName;
 requestLog.ActionName = filterContext.ActionDescriptor.ActionName;
 requestLog.FunctionalModule = this.FunctionalModule;
 requestLog.OperationType = this.OperationType;
 requestLog.OperationDate = DateTime.Now;
 requestLog.Path = filterContext.RequestContext.HttpContext.Request.Path;
 requestLog.Params = GetStrPatams(filterContext.RequestContext.HttpContext.Request);
 
 //记录日志
 string logJson = JsonConvert.SerializeObject(requestLog);
 WriteLog(logJson);
 }
 
 /// <summary>
 /// 获取字符串参数
 /// </summary>
 public string GetStrPatams(HttpRequestBase theRequest)
 {
 string result = "";
 string url = theRequest.Url.ToString();
 
 string method = theRequest.HttpMethod;
 if (method == "GET")
 {
 result = theRequest.QueryString.ToString();
 }
 else if (method == "POST")
 {
 result = theRequest.Form.ToString();
 }
 
 //if (result == "")
 //{
 // result = theRequest.Params.ToString();
 //}
 
 if (result.Length > 0)
 {
 result = HttpUtility.UrlDecode(result, Encoding.UTF8);
 }
 
 return result;
 }
 
 /// <summary>
 /// 写入日志
 /// </summary>
 public void WriteLog(string message)
 {
 string path = AppDomain.CurrentDomain.BaseDirectory + "/MyLog.txt";
 using (StreamWriter sw = new StreamWriter(path, true, Encoding.Default))
 {
 sw.Flush();
 sw.WriteLine("时间：" + DateTime.Now);
 sw.WriteLine("内容：" + message);
 sw.WriteLine("-------------------------");
 }
 }
 }
 }

创建OrderController.cs（订单控制器），编写新增订单方法，并在该方法上添加OperateLog特性：

using MvcApp.Filter;
 using MvcApp.Models;
 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Web;
 using System.Web.Mvc;
 
 namespace MvcApp.Controllers
 {
 /// <summary>
 /// 订单控制器
 /// </summary>
 public class OrderController : Controller
 {
 /// <summary>
 /// 新增订单
 /// </summary>
 [OperateLog(FunctionalModule = "订单业务", OperationType = "新增")]
 public bool AddOrder(string orderName, decimal price)
 {
 return true;
 }
 }
 }

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3Bhbl9qdW5iaWFv_size_16_color_FFFFFF_t_70]: /images/20210724/bd50c1b7068542488b36c3e30a49dd2c.png