Controller级别的异常处理过滤器IExceptionFilter

1，系统自带的HandleErrorAttribute类继承自IExceptionFilter，是MVC的默认实现。

同时设置web.config 

<system.web>
<customErrors mode="On"/>

</system.web>

//只需要简单的将改特性放到controller类头上，告诉MVC如果该Controller中的Action方法出现异常，都交由HandleError特性处理
[HandleError(ExceptionType = typeof(System.Data.DataException), View = "Error")]
public class HomeController : Controller{
/* Controller Actions with HandleError applied to them */
}

HandleErrorAttribute类中OnException方法的源代码如下：

// System.Web.Mvc.HandleErrorAttribute
public virtual void OnException(ExceptionContext filterContext)
{
    if (filterContext == null)
    {
        throw new ArgumentNullException("filterContext");
    }
    if (filterContext.IsChildAction)
    {
        return;
    }
    if (filterContext.ExceptionHandled || !filterContext.HttpContext.IsCustomErrorEnabled)
    {
        return;
    }
    Exception exception = filterContext.Exception;
    if (new HttpException(null, exception).GetHttpCode() != 500)
    {
        return;
    }
    if (!this.ExceptionType.IsInstanceOfType(exception))
    {
        return;
    }
    string controllerName = (string)filterContext.RouteData.Values["controller"];
    string actionName = (string)filterContext.RouteData.Values["action"];
    HandleErrorInfo model = new HandleErrorInfo(filterContext.Exception, controllerName, actionName);
    filterContext.Result = new ViewResult
    {
        ViewName = this.View,
        MasterName = this.Master,
        ViewData = new ViewDataDictionary<HandleErrorInfo>(model),
        TempData = filterContext.Controller.TempData
    };
    filterContext.ExceptionHandled = true;
    filterContext.HttpContext.Response.Clear();
    filterContext.HttpContext.Response.StatusCode = 500;
    filterContext.HttpContext.Response.TrySkipIisCustomErrors = true;
}

2，自定义方式

方式一：

可以重写自定义过滤器，重写HandleErrorAttribute类中的OnException方法

同样设置web.config

<system.web>
<customErrors mode="On"/>
</system.web>

public class MyHandleErrorAttribute : HandleErrorAttribute 
{
   public override void OnException(ExceptionContext filterContext)
   {
     //自定义
   }
}

 然后，把自定义过滤器“MyHandleError”放到Controller的头上即可,

[MyHandleError(ExceptionType = typeof(System.Data.DataException), View = "Error")]
public class HomeController : Controller{
/* Controller Actions with HandleError applied to them */
}

方式二：

System.Web.Mvc.Controller类，也继承自IExceptionFilter，但是没有实现OnException方法，因此可以在Controller下重写（实现）OnException方法

同样设置web.config

<system.web>
<customErrors mode="On"/>
</system.web>

public class BaseController : Controller
    {
protected override void OnException(ExceptionContext filterContext)
        {
            base.OnException(filterContext);

            // 当自定义显示错误 mode = On，显示友好错误页面
            if (filterContext.HttpContext.IsCustomErrorEnabled)
            {
                filterContext.ExceptionHandled = true;
                this.View("Error").ExecuteResult(this.ControllerContext);
            }
        }
    }