ASP.NET MVC 修改视图的默认路径
作者：互联网
本章将和大家分享如何在ASP.NET MVC中修改视图的默认路径。在此之前，首先我们要搞懂MVC它是怎么搜索视图的。
先来看下Demo的目录结构：
本Demo的Web项目为ASP.NET Web 应用程序（目标框架为.NET Framework 4.5） MVC项目。
众所周知在Action中如果要返回一个页面，那我们一般的做法都是去调用View方法，如下所示：
接下来我们就通过反编译工具来看一下这个View方法里面到底都做了啥：
可以看到它最后返回的是 ViewResult 对象，我们继续通过反编译工具来看一下这个 ViewResult 类：
可以发现，它是从 base.ViewEngineCollection 中找默认视图的，下面我们继续通过反编译工具找到 base.ViewEngineCollection ，如下所示：
可以看到，其实它返回就是一个 ViewEngineCollection 视图引擎集合，并且它的取值来自 ViewEngines.Engines ，我们点击 Engines 往里找：
继续点击 _engines 往里找：
找到最后我们可以发现，其实 ViewEngines.Engines 里面存放的就是 new WebFormViewEngine() 和 new RazorViewEngine() 。
我们继续通过反编译工具找到 RazorViewEngine 这个类，如下所示：
using System;
namespace System.Web.Mvc
{
/// <summary>Represents a view engine that is used to render a Web page that uses the ASP.NET Razor syntax.</summary>
public class RazorViewEngine : BuildManagerViewEngine
{
internal static readonly string ViewStartFileName = "_ViewStart";
/// <summary>Initializes a new instance of the <see cref="T:System.Web.Mvc.RazorViewEngine" /> class.</summary>
public RazorViewEngine() : this(null)
{
}
/// <summary>Initializes a new instance of the <see cref="T:System.Web.Mvc.RazorViewEngine" /> class using the view page activator.</summary>
/// <param name="viewPageActivator">The view page activator.</param>
public RazorViewEngine(IViewPageActivator viewPageActivator) : base(viewPageActivator)
{
base.AreaViewLocationFormats = new string[]
{
"~/Areas/{2}/Views/{1}/{0}.cshtml",
"~/Areas/{2}/Views/{1}/{0}.vbhtml",
"~/Areas/{2}/Views/Shared/{0}.cshtml",
"~/Areas/{2}/Views/Shared/{0}.vbhtml"
};
base.AreaMasterLocationFormats = new string[]
{
"~/Areas/{2}/Views/{1}/{0}.cshtml",
"~/Areas/{2}/Views/{1}/{0}.vbhtml",
"~/Areas/{2}/Views/Shared/{0}.cshtml",
"~/Areas/{2}/Views/Shared/{0}.vbhtml"
};
base.AreaPartialViewLocationFormats = new string[]
{
"~/Areas/{2}/Views/{1}/{0}.cshtml",
"~/Areas/{2}/Views/{1}/{0}.vbhtml",
"~/Areas/{2}/Views/Shared/{0}.cshtml",
"~/Areas/{2}/Views/Shared/{0}.vbhtml"
};
base.ViewLocationFormats = new string[]
{
"~/Views/{1}/{0}.cshtml",
"~/Views/{1}/{0}.vbhtml",
"~/Views/Shared/{0}.cshtml",
"~/Views/Shared/{0}.vbhtml"
};
base.MasterLocationFormats = new string[]
{
"~/Views/{1}/{0}.cshtml",
"~/Views/{1}/{0}.vbhtml",
"~/Views/Shared/{0}.cshtml",
"~/Views/Shared/{0}.vbhtml"
};
base.PartialViewLocationFormats = new string[]
{
"~/Views/{1}/{0}.cshtml",
"~/Views/{1}/{0}.vbhtml",
"~/Views/Shared/{0}.cshtml",
"~/Views/Shared/{0}.vbhtml"
};
base.FileExtensions = new string[]
{
"cshtml",
"vbhtml"
};
}
/// <summary>Creates a partial view using the specified controller context and partial path.</summary>
/// <returns>The partial view.</returns>
/// <param name="controllerContext">The controller context.</param>
/// <param name="partialPath">The path to the partial view.</param>
protected override IView CreatePartialView(ControllerContext controllerContext, string partialPath)
{
return new RazorView(controllerContext, partialPath, null, false, base.FileExtensions, base.ViewPageActivator)
{
DisplayModeProvider = base.DisplayModeProvider
};
}
/// <summary>Creates a view by using the specified controller context and the paths of the view and master view.</summary>
/// <returns>The view.</returns>
/// <param name="controllerContext">The controller context.</param>
/// <param name="viewPath">The path to the view.</param>
/// <param name="masterPath">The path to the master view.</param>
protected override IView CreateView(ControllerContext controllerContext, string viewPath, string masterPath)
{
return new RazorView(controllerContext, viewPath, masterPath, true, base.FileExtensions, base.ViewPageActivator)
{
DisplayModeProvider = base.DisplayModeProvider
};
}
}
}
可以惊奇的发现，上面描述的路径就是我们MVC默认的视图路径。既然如此，那我们大概知道了，将来如果要做一些扩展（例如：修改MVC默认的视图路径），就可以从这个类入手。
话不多说，下面我们重点来看下如何修改MVC默认的视图路径？
首先我们先来验证下 ViewEngines.Engines 里面存放的到底是不是只有 new WebFormViewEngine() 和 new RazorViewEngine() ，如下所示：
我们调试 Global.asax 中 Application_Start 方法，可以发现 ViewEngines.Engines 里面存的确实只有 new WebFormViewEngine() 和 new RazorViewEngine() ，那么下面我们就可以大胆的去扩展了。
自定义一个Razor视图引擎，如下所示：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
namespace ViewEngineExtend.ViewEngineExtend
{
/// <summary>
/// 自定义Razor视图引擎
/// </summary>
public class CustomRazorViewEngine : RazorViewEngine
{
#region 构造函数
public CustomRazorViewEngine()
: this(null)
{
}
public CustomRazorViewEngine(IViewPageActivator viewPageActivator)
: base(viewPageActivator)
{
}
#endregion 构造函数
public override ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName, bool useCache)
{
if (controllerContext.HttpContext.Request.UserAgent.Contains("Chrome"))
{
this.SetTheme("Chrome");
}
else
{
this.SetTheme(""); //一定得有，因为只有一个Engines实例
}
return base.FindView(controllerContext, viewName, masterName, useCache);
}
public override ViewEngineResult FindPartialView(ControllerContext controllerContext, string partialViewName, bool useCache)
{
if (controllerContext.HttpContext.Request.UserAgent.Contains("Chrome"))
{
this.SetTheme("Chrome");
}
else
{
this.SetTheme(""); //一定得有，因为只有一个Engines实例
}
return base.FindPartialView(controllerContext, partialViewName, useCache);
}
/// <summary>
/// 设置主题（修改视图的默认路径）
/// </summary>
/// <param name="browser">浏览器</param>
void SetTheme(string browser)
{
if (!string.IsNullOrEmpty(browser) && browser.Contains("Chrome"))
{
base.AreaViewLocationFormats = new string[]
{
"~/Areas/{2}/ChromeViews/{1}/{0}.cshtml",
"~/Areas/{2}/ChromeViews/{1}/{0}.vbhtml",
"~/Areas/{2}/ChromeViews/Shared/{0}.cshtml",
"~/Areas/{2}/ChromeViews/Shared/{0}.vbhtml"
};
base.AreaMasterLocationFormats = new string[]
{
"~/Areas/{2}/ChromeViews/{1}/{0}.cshtml",
"~/Areas/{2}/ChromeViews/{1}/{0}.vbhtml",
"~/Areas/{2}/ChromeViews/Shared/{0}.cshtml",
"~/Areas/{2}/ChromeViews/Shared/{0}.vbhtml"
};
base.AreaPartialViewLocationFormats = new string[]
{
"~/Areas/{2}/ChromeViews/{1}/{0}.cshtml",
"~/Areas/{2}/ChromeViews/{1}/{0}.vbhtml",
"~/Areas/{2}/ChromeViews/Shared/{0}.cshtml",
"~/Areas/{2}/ChromeViews/Shared/{0}.vbhtml"
};
base.ViewLocationFormats = new string[]
{
"~/ChromeViews/{1}/{0}.cshtml",
"~/ChromeViews/{1}/{0}.vbhtml",
"~/ChromeViews/Shared/{0}.cshtml",
"~/ChromeViews/Shared/{0}.vbhtml"
};
base.MasterLocationFormats = new string[]
{
"~/ChromeViews/{1}/{0}.cshtml",
"~/ChromeViews/{1}/{0}.vbhtml",
"~/ChromeViews/Shared/{0}.cshtml",
"~/ChromeViews/Shared/{0}.vbhtml"
};
base.PartialViewLocationFormats = new string[]
{
"~/ChromeViews/{1}/{0}.cshtml",
"~/ChromeViews/{1}/{0}.vbhtml",
"~/ChromeViews/Shared/{0}.cshtml",
"~/ChromeViews/Shared/{0}.vbhtml"
};
}
else
{
base.AreaViewLocationFormats = new string[]
{
"~/Areas/{2}/Views/{1}/{0}.cshtml",
"~/Areas/{2}/Views/{1}/{0}.vbhtml",
"~/Areas/{2}/Views/Shared/{0}.cshtml",
"~/Areas/{2}/Views/Shared/{0}.vbhtml"
};
base.AreaMasterLocationFormats = new string[]
{
"~/Areas/{2}/Views/{1}/{0}.cshtml",
"~/Areas/{2}/Views/{1}/{0}.vbhtml",
"~/Areas/{2}/Views/Shared/{0}.cshtml",
"~/Areas/{2}/Views/Shared/{0}.vbhtml"
};
base.AreaPartialViewLocationFormats = new string[]
{
"~/Areas/{2}/Views/{1}/{0}.cshtml",
"~/Areas/{2}/Views/{1}/{0}.vbhtml",
"~/Areas/{2}/Views/Shared/{0}.cshtml",
"~/Areas/{2}/Views/Shared/{0}.vbhtml"
};
base.ViewLocationFormats = new string[]
{
"~/Views/{1}/{0}.cshtml",
"~/Views/{1}/{0}.vbhtml",
"~/Views/Shared/{0}.cshtml",
"~/Views/Shared/{0}.vbhtml"
};
base.MasterLocationFormats = new string[]
{
"~/Views/{1}/{0}.cshtml",
"~/Views/{1}/{0}.vbhtml",
"~/Views/Shared/{0}.cshtml",
"~/Views/Shared/{0}.vbhtml"
};
base.PartialViewLocationFormats = new string[]
{
"~/Views/{1}/{0}.cshtml",
"~/Views/{1}/{0}.vbhtml",
"~/Views/Shared/{0}.cshtml",
"~/Views/Shared/{0}.vbhtml"
};
//base.FileExtensions = new string[]
//{
// "cshtml",
// "vbhtml"
//};
}
}
}
}
接着修改 Global.asax 中 Application_Start 方法，将默认的 RazorViewEngine 替换成自定义的 CustomRazorViewEngine ，如下所示：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Optimization;
using System.Web.Routing;
using ViewEngineExtend.ViewEngineExtend;
namespace ViewEngineExtend
{
public class MvcApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
//var viewEngineCollection = ViewEngines.Engines;
ViewEngines.Engines.Clear();
ViewEngines.Engines.Add(new WebFormViewEngine());
ViewEngines.Engines.Add(new CustomRazorViewEngine()); //替换成自定义的Razor视图引擎
}
}
}
此外，Demo中还准备了两套视图：
其中 ~/ChromeViews/Home/Index.cshtml 代码如下所示：
@{
ViewBag.Title = "Home Page";
}
<h1>This is ChromeViews/Home/Index</h1>
其中 ~/Views/Home/Index.cshtml 代码如下所示：
@{
ViewBag.Title = "Home Page";
}
<h1>This is Views/Home/Index</h1>
最后，我们分别使用 谷歌浏览器和IE浏览器 来访问 /Home/Index 页面，如下所示：
谷歌浏览器运行结果如下：
IE浏览器运行结果如下：
可以发现这两个浏览器的运行结果是不一样的，说明我们的视图引擎扩展成功了。
至此本文就全部介绍完了，如果觉得对您有所启发请记得点个赞哦！！！
Demo源码：
链接：https://pan.baidu.com/s/1TWVlsq98Sjt6qYOMXaTwCQ 提取码：3nm2
此文由博主精心撰写转载请保留此原文链接：https://www.cnblogs.com/xyh9039/p/15240321.html
版权声明：如有雷同纯属巧合，如有侵权请及时联系本人修改，谢谢！！！
标签：ASP,Views,视图,vbhtml,MVC,cshtml,Shared,new,Areas 来源： https://www.cnblogs.com/xyh9039/p/15240321.html