How to add assembly in web.config file of mvc 4

Question

I have a "MVC 4" project and i want to add an assembly to web.config file but i don't know where should i put it. I try any ways but i cant find the solution.

every time i got this error:

You must add a reference to assembly 'System.Data.Entity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'.

this is my web.config file:

    <?xml version="1.0" encoding="utf-8"?>
<!--
  For more information on how to configure your ASP.NET application, please visit
  http://go.microsoft.com/fwlink/?LinkId=152368
  -->
<configuration>
  <connectionStrings>
    <add name="ParsGraphicEntities" connectionString="metadata=res://*/Entities.ParsGraphic.csdl|res://*/Entities.ParsGraphic.ssdl|res://*/Entities.ParsGraphic.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=.;initial catalog=ParsGraphic;integrated security=True;multipleactiveresultsets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" />
    <add name="DefaultConnection" connectionString="Data Source=.\SQLEXPRESS;Initial Catalog=aspnet-UI.MVC.InternetApplication-2012317193118;Integrated Security=True" providerName="System.Data.SqlClient" />
  </connectionStrings>
  <appSettings>
    <add key="webpages:Version" value="2.0.0.0" />
    <add key="webpages:Enabled" value="true" />
    <add key="PreserveLoginUrl" value="true" />
    <add key="ClientValidationEnabled" value="true" />
    <add key="UnobtrusiveJavaScriptEnabled" value="true" />
  </appSettings>
  <system.web>
    <compilation debug="true" targetFramework="4.0" />
    <authentication mode="Forms">
      <forms loginUrl="~/Account/Login" timeout="2880" />
    </authentication>
    <pages>
      <namespaces>
        <add namespace="System.Web.Helpers" />
        <add namespace="System.Web.Mvc" />
        <add namespace="System.Web.Mvc.Ajax" />
        <add namespace="System.Web.Mvc.Html" />
        <add namespace="System.Web.Routing" />
        <add namespace="System.Web.WebPages" />
      </namespaces>
    </pages>
    <profile defaultProvider="DefaultProfileProvider">
      <providers>
        <add name="DefaultProfileProvider" type="System.Web.Providers.DefaultProfileProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" applicationName="/" />
      </providers>
    </profile>
    <membership defaultProvider="DefaultMembershipProvider">
      <providers>
        <add name="DefaultMembershipProvider" type="System.Web.Providers.DefaultMembershipProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10" applicationName="/" />
      </providers>
    </membership>
    <roleManager defaultProvider="DefaultRoleProvider">
      <providers>
        <add name="DefaultRoleProvider" type="System.Web.Providers.DefaultRoleProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" applicationName="/" />
      </providers>
    </roleManager>
    <sessionState mode="InProc" customProvider="DefaultSessionProvider">
      <providers>
        <add name="DefaultSessionProvider" type="System.Web.Providers.DefaultSessionStateProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" applicationName="/" />
      </providers>
    </sessionState>
  </system.web>
  <system.webServer>
    <validation validateIntegratedModeConfiguration="false" />
    <modules runAllManagedModulesForAllRequests="true" />
  </system.webServer>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-2.0.0.0" newVersion="2.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-4.0.0.0" newVersion="4.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-2.0.0.0" newVersion="2.0.0.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
</configuration>

please help me.

thanks.

Solution 1

It is quite simple. Look at your compilation section in your web.config:

<compilation debug="true" targetFramework="4.0"/>

Now open the section and put your assembly inside like this:

<compilation debug="true" targetFramework="4.0">
  <assemblies>
    <add assembly="System.Data.Entity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
  </assemblies>
</compilation>

Libraries in this section are checked in compilation time, it has nothing to do with runtime binding.

Solution 2

I just experienced the same issue with MVC 4 in VS Express 2012 for Web, but, while Alfonso's answer was much more helpful than anything else I found on the Web, it unfortunately did not clear up the error in my project. After doing some research on the Internet (to no avail) and then just poking around Visual Studio, I found the following solution.

In addition to adding EntityFramework to my project's references and adding the tag to my Web.config, I also had to take the following steps to satisfy the compiler:

1. Right-click the References folder > Add Reference...
2. Expand Assemblies on the left side of the window and select Framework.
3. Scroll to and select System.Data.Entity in the list of assemblies.
4. Make sure the box next to System.Data.Entity is checked, then click 'OK'.
5. Rebuild the project.