'无法加载文件或程序集'System.Web.Helpers'或其依赖项之一

Question

我在尝试运行我的 ASP.NET 项目时遇到以下错误。谁能给点建议？

Could not load file or assembly 'System.Web.Helpers' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.IO.FileLoadException: Could not load file or assembly 'System.Web.Helpers' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)

Source Error: 

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Assembly Load Trace: The following information can be helpful to determine why the assembly 'System.Web.Helpers' could not be loaded.


=== Pre-bind state information ===
LOG: DisplayName = System.Web.Helpers
 (Partial)
WRN: Partial binding information was supplied for an assembly:
WRN: Assembly Name: System.Web.Helpers | Domain ID: 2
WRN: A partial bind occurs when only part of the assembly display name is provided.
WRN: This might result in the binder loading an incorrect assembly.
WRN: It is recommended to provide a fully specified textual identity for the assembly,
WRN: that consists of the simple name, version, culture, and public key token.
WRN: See whitepaper http://go.microsoft.com/fwlink/?LinkId=109270 for more information and common solutions to this issue.
LOG: Appbase = .../.../
LOG: Initial PrivatePath = \...\WebInterface\bin
Calling assembly : (Unknown).
===
LOG: This bind starts in default load context.
LOG: Using application configuration file: \...\WebInterface\web.config
LOG: Using host configuration file: \Documents\IISExpress\config\aspnet.config
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config.
LOG: Policy not being applied to reference at this time (private, custom, partial, or location-based assembly bind).
LOG: Attempting download of new URL /AppData/Local/Temp/Temporary ASP.NET Files/vs/0418a60d/21ffd41/System.Web.Helpers.DLL.
LOG: Attempting download of new URL /AppData/Local/Temp/Temporary ASP.NET Files/vs/0418a60d/21ffd41/System.Web.Helpers/System.Web.Helpers.DLL.
LOG: Attempting download of new URL .../.../bin/System.Web.Helpers.DLL.
LOG: Using application configuration file: \...\WebInterface\web.config
LOG: Using host configuration file: \Documents\IISExpress\config\aspnet.config
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config.
LOG: Redirect found in application configuration file: 2.0.0.0 redirected to 3.0.0.0.
LOG: Post-policy reference: System.Web.Helpers, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
LOG: Attempting download of new URL /AppData/Local/Temp/Temporary ASP.NET Files/vs/0418a60d/21ffd41/System.Web.Helpers.DLL.
LOG: Attempting download of new URL /AppData/Local/Temp/Temporary ASP.NET Files/vs/0418a60d/21ffd41/System.Web.Helpers/System.Web.Helpers.DLL.
LOG: Attempting download of new URL .../.../bin/System.Web.Helpers.DLL.
WRN: Comparing the assembly name resulted in the mismatch: Major Version
ERR: Failed to complete setup of assembly (hr = 0x80131040). Probing terminated.

Stack Trace: 


[FileLoadException: Could not load file or assembly 'System.Web.Helpers' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)]

[FileLoadException: Could not load file or assembly 'System.Web.Helpers, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)]
   System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +0
   System.Reflection.RuntimeAssembly.nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +36
   System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +152
   System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean forIntrospection) +77
   System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection) +21
   System.Reflection.Assembly.Load(String assemblyString) +28
   System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective) +38

[ConfigurationErrorsException: Could not load file or assembly 'System.Web.Helpers, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)]
   System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective) +738
   System.Web.Configuration.CompilationSection.LoadAllAssembliesFromAppDomainBinDirectory() +217
   System.Web.Configuration.CompilationSection.LoadAssembly(AssemblyInfo ai) +130
   System.Web.Compilation.BuildManager.GetReferencedAssemblies(CompilationSection compConfig) +170
   System.Web.Compilation.BuildManager.GetPreStartInitMethodsFromReferencedAssemblies() +92
   System.Web.Compilation.BuildManager.CallPreStartInitMethods(String preStartInitListPath, Boolean& isRefAssemblyLoaded) +290
   System.Web.Compilation.BuildManager.ExecutePreAppStart() +157
   System.Web.Hosting.HostingEnvironment.Initialize(ApplicationManager appManager, IApplicationHost appHost, IConfigMapPathFactory configMapPathFactory, HostingEnvironmentParameters hostingParameters, PolicyLevel policyLevel, Exception appDomainCreationException) +531

[HttpException (0x80004005): Could not load file or assembly 'System.Web.Helpers, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)]
   System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +9963380
   System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +101
   System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +254

我根据其他答案尝试了以下方法：

• 与https://www.microsoft.com/en-us/download/details.aspx?id=30683 分开安装 ASP.NET MVC 4
• 更新 NuGet 包
• 设置 System.Web.Helpers 将本地复制为 True

Answer 1

项目中 System.Web.Helpers 程序集的引用版本可能与 web.config 文件中提到的版本不匹配。按照下面提到的步骤。

1. 检查 System.Web.Helpers 的引用版本。
2. 查看web应用根目录下的web.config文件，看是否有System.Web.Helpers的入口，与参考版本一致。
3. 查看Web应用的“Views”文件夹下的web.config文件，看是否有System.Web.Helpers的入口，与参考版本一致。

Answer 2

我遇到了这个问题。这是当我将 Razor 视图添加到 Web 窗体项目时引起的。由于这个动作，Visual Studio 添加了 .Net 版本 5 并对项目进行了大量其他修改。

我通过进入Solution Explorer > Pending Changes 解决了这个问题。我观察到列出了一大堆不寻常的文件。我右键单击任何文件并转到Source Control > Undo Pending Changes。我选择了不寻常的文件和Undo Changes，重建后它被修复了。

我在其他时候也看到了这些额外的文件被添加（没有明显的原因）。 Visual Studio 做的一些乱七八糟的事情我不清楚。

Answer 3

我在创建新的 Razor 视图时也遇到了这个问题。该项目正在寻找更新版本的 System.Web.Helper 和 System.Web.WebPages dll。我通过编辑我的 web.config 并将 newVersion 从 3.0.0.0 更改为 2.0.0.0 解决了这个问题。您也可以像我一样从 web.config 中完全删除这些内容。

 <dependentAssembly>
    <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
    <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="2.0.0.0" />
  </dependentAssembly>
  <dependentAssembly>
    <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
    <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="2.0.0.0" />
  </dependentAssembly>

Answer 4

我遇到了这个问题，并尝试了所有相同的方法来解决它。他们都没有工作。我最终从另一个项目中手动复制了 dll 文件。将它放在项目/bin 文件夹中。我的几个扩展都有这个问题，我不确定是什么原因造成的。

Answer 5

在解决方案资源管理器中选择 System.Web.Helpers，而不是在属性面板中将“复制本地”设置更改为“假”。这对我有用。