blocks|key|3428321|text|通过尝试和错误，我找到了导致错误的代码行(是DbContext+ctor)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3428322|public+class+MyThingDb+:+DbContext
{
++++//+If+I+comment+this+constructor+out+the+scaffolding+works
++++public+MyThingDb()
++++++++:+base("DefaultConnection")
++++{
++++}

++++public+DbSet<MyThing>+Things{+get;+set;+}
}|code-block|syntax|javascript|3428323|见鬼？|3428324|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

By trial and error I found the line of code (it's the DbContext ctor) that is causing the error:

<pre><code>public class MyThingDb : DbContext
{
 // If I comment this constructor out the scaffolding works
 public MyThingDb()
 : base("DefaultConnection")
 {
 }

 public DbSet&lt;MyThing&gt; Things{ get; set; }
}
</code></pre>

WTF?

blocks|key|4309769|text|在运行一个关于构建MVC音乐商店应用程序的教程时，我也无意中发现了这个症状。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4309770|显然，Visual中存在一个bug。触发此错误的似乎是选择用于连接字符串的某些名称，而不是默认名称。|4309771|我感谢http://forums.asp.net/t/1838396.aspx/1上的用户dwaynef找到了这个解决办法。|offset|length|4309772|在添加新的脚手架控制器期间，您需要暂时将连接字符串的名称更改为“DefaultConnection”(web.config)：|4309773|<connectionStrings>
+++++<add+name="DefaultConnection"+...+/>
</connectionStrings>|code-block|syntax|javascript|4309774|如果您有多个连接字符串--在执行操作时确保只有这个连接字符串。|4309775|entityMap|0|LINK|mutability|MUTABLE|url|http://forums.asp.net/t/1838396.aspx/1^0|0|0|3|12|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Z|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|10|8|@]|9|@$F|11|G|12|1|13]]|A|$]]|$1|H|3|I|5|6|7|14|8|@]|9|@]|A|$]]|$1|J|3|K|5|L|7|15|8|@]|9|@]|A|$M|N]]|$1|O|3|P|5|6|7|16|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|17|8|@]|9|@]|A|$]]]|R|$S|$5|T|U|V|A|$W|X]]]]

I also stumbled into this symptom while running a tutorial on the subject of building an MVC Music Store application.

There definitely seem to be a bug within Visual Studio. What seems to trigger this bug is choosing some name, other than the default, used for the connection string.

My thanks goes to user dwaynef on <a href="http://forums.asp.net/t/1838396.aspx/1">http://forums.asp.net/t/1838396.aspx/1</a> for finding this workaround.

A bit elaborated you need to, temporarily during addition of the new scaffolding controller, change the name of your connection string to 'DefaultConnection' in web.config:

<pre><code>&lt;connectionStrings&gt;
 &lt;add name="DefaultConnection" ... /&gt;
&lt;/connectionStrings&gt;
</code></pre>

If you have more than one connection string - make sure only this one is there while performing the action.

blocks|key|3451928|text|我也有类似的问题，但它不是默认的构造函数。如果解决方案中有多个项目，而面向MVC项目的"Web“不引用EntityFramework，也会发生这种情况。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3451929|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I had a similar issue but it wasn't the default constructor. It also happens if you have multiple projects in your solution and your "Web" facing MVC project does not reference EntityFramework.

blocks|key|3451957|text|这是我的两分钱。我不相信你的解决方案真的能解决问题。真正的修复方法是传递基本构造函数数据库名，而不是连接字符串名，因此如果连接字符串是|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3451958|<add+name="MyContext"+connectionString="Data+Source=%7CDataDirectory%7CMyDatabase.sdf"+providerName="System.Data.SqlServerCe.4.0"+/>|code-block|syntax|javascript|3451959|您的上下文类应该定义为|3451960|++++public+class+MyContext+:+DbContext+
{
++++public+MyContext()+:+base("MyDatabase")+{+}...+|3451961|希望这对你和其他人有用，就像对我一样。|3451962|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Here's my two cents worth. I don't believe your solution actually addresses the real issue. The real fix is to pass the base constructor the database name rather than the connection string name so if your connection string is 

<pre><code>&lt;add name="MyContext" connectionString="Data Source=|DataDirectory|MyDatabase.sdf" providerName="System.Data.SqlServerCe.4.0" /&gt;
</code></pre>

you're context class should be defined as 

<pre><code> public class MyContext : DbContext 
{
 public MyContext() : base("MyDatabase") { }... 
</code></pre>

Hope this works for you and others as it does for me.

blocks|key|4309851|text|在尝试了不同的选项之后，下面的方法解决了错误。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4309852|如果连接字符串中的名称值与传递给构造函数的值匹配，则它可以工作。|4309853|+public+MyThingDb()
++++++++:+base("name=MyContext")
++++{
++++}|code-block|syntax|javascript|4309854|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

After trying different options, the below method resolves the error..

If the name value in connection string matches with the value passed to the constructor, it works.

<pre><code> public MyThingDb()
 : base("name=MyContext")
 {
 }
</code></pre>

blocks|key|4309892|text|改变里面的“东西”|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4309893|public
DbSet<MyThing>+Things
{+get;+set;+}
}|code-block|syntax|javascript|4309894|到"Database1“，其中"Database1”是磁盘上数据库文件的名称，在Web.config文件中显示为"Database1.sdf“|offset|length|style|CODE|4309895|entityMap^0|0|0|14|A|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Change "Things" inside 

<pre><code>public
DbSet&lt;MyThing&gt; Things
{ get; set; }
}
</code></pre>

to
"Database1" where "Database1" is the name of the database file on disk which appears in your <code>Web.config</code> file as "Database1.sdf"

blocks|key|3428479|text|以下是对我起作用的东西：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3428480|转到web.config中的连接字符串，更改以下内容：providerName="System.Data.SqlClient"|unordered-list-item|offset|length|style|CODE|3428481|3428482|3428483|而不是|3428484|providerName="System.Data.SqlServerCe.4.0"|3428485|生成控制器。|3428486|将providerName重命名为"System.Data.SqlServerCe.4.0“。|3428487|运行你的项目。|3428488|3428489|3428490|entityMap^0|0|R|10|0|0|0|0|0|16|0|0|I|R|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@$E|10|F|11|G|H]]|9|@]|A|$]]|$1|I|3|-4|5|6|7|12|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|13|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|14|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|15|8|@$E|16|F|17|G|H]]|9|@]|A|$]]|$1|O|3|P|5|D|7|18|8|@]|9|@]|A|$]]|$1|Q|3|R|5|D|7|19|8|@$E|1A|F|1B|G|H]]|9|@]|A|$]]|$1|S|3|T|5|D|7|1C|8|@]|9|@]|A|$]]|$1|U|3|-4|5|6|7|1D|8|@]|9|@]|A|$]]|$1|V|3|-4|5|6|7|1E|8|@]|9|@]|A|$]]|$1|W|3|-4|5|6|7|1F|8|@]|9|@]|A|$]]]|X|$]]

Here is what worked for me:

<ul>
<li>Go to connection string in web.config change the following:
<code>providerName="System.Data.SqlClient"</code> </li>
</ul>

instead of 

<code>providerName="System.Data.SqlServerCe.4.0"</code>

<ul>
<li>Generate your controller.</li>
<li>Rename providerName back to "<code>System.Data.SqlServerCe.4.0</code>".</li>
<li>run your project.</li>
</ul>

blocks|key|3452042|text|对我起作用的解决方案是将与连接字符串中的数据库名称相同的数据库名称传递给dbContext类的基本恒序器。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3452043|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

The solution that worked for me is to pass the same database name as in your connection string to the base constactor of your dbContext class.

blocks|key|3452063|text|这就是我想出来的..。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3452064|我使用'System.Data.SqlServerCe.4.0‘注释掉了连接字符串，然后添加了带有脚手架模板的控制器。|3452065|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

This is what that worked out for me ..

I commented out the connectionstring using the 'System.Data.SqlServerCe.4.0' and 
then added the controller with scaffolding templates.

blocks|key|4309959|text|我通过在添加控制器之前按CTRL%2BF5重新构建我的项目来解决这个问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4309960|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I solved this by pressing CTRL+F5 to rebuild my project before adding my controller.

blocks|key|3428621|text|问题可能是由于模型类中缺少[NotMapped]属性。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3428622|因为我错过了这个属性，而且我的头很狡猾。|3428623|[Display(Name="Logo")]
[DataType(DataType.Upload)]
[NotMapped]
public+HttpPostedFileBase+Logo+{+set;+get;+}|code-block|syntax|javascript|3428624|entityMap^0|D|B|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|S|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

Problem may be because of missing
<code>[NotMapped]</code> Attribute
in one of the model class.

As I missed the attribute and I was cunning my head.

<pre><code>[Display(Name="Logo")]
[DataType(DataType.Upload)]
[NotMapped]
public HttpPostedFileBase Logo { set; get; }
</code></pre>

blocks|key|4310034|text|为我工作:在“添加新的脚手架项目”对话框中，我添加了一个新的上下文(加号)和任何名称(用于我的"ScaffoldingContext")。然后脚手架就能工作了。只需在Controller中重命名上下文即可。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4310035|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Works for me:
In the "Add New Scaffolded Item" dialog, i added a new context (plus) with any name (for me "ScaffoldingContext").
Then the scaffolding works. Just rename the context in the Controller.

blocks|key|3428664|text|在上下文类中，当要创建带有脚手架的控制器时，必须注释DbConfigurationType。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3428665|//[DbConfigurationType(typeof(MySql.Data.Entity.MySqlEFConfiguration))]
public+class+NameDbContext+
{}|code-block|syntax|javascript|3428666|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

In your context class you have to comment the DbConfigurationType when you are going to create a controller with scaffolding.

<pre><code>//[DbConfigurationType(typeof(MySql.Data.Entity.MySqlEFConfiguration))]
public class NameDbContext 
{}
</code></pre>

blocks|key|4310090|text|这有时可能是由关联属性或外键属性引起的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4310091|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

This may sometimes be caused by an association property or a foreign key attribute

blocks|key|3428759|text|MVC+5/+EF+6|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3428760|也许你可以在旧版本中做到这一点？|3428761|注释掉web+/+app.config中的连接字符串，然后保存|ordered-list-item|3428762|尝试创建新控制器并让VS创建一个“新”dbcontext项，而不是选择您已经拥有的|3428763|单击create|3428764|删除新的dbcontext类|3428765|将控制器dbcontext替换为您的|3428766|取消web+/+app.config中的连接字符串，然后保存|3428767|3428768|3428769|为我工作！|3428770|entityMap^0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|Z|8|@]|9|@]|A|$]]|$1|I|3|J|5|F|7|10|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|11|8|@]|9|@]|A|$]]|$1|M|3|N|5|F|7|12|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|13|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|14|8|@]|9|@]|A|$]]|$1|R|3|-4|5|6|7|15|8|@]|9|@]|A|$]]|$1|S|3|T|5|6|7|16|8|@]|9|@]|A|$]]|$1|U|3|-4|5|6|7|17|8|@]|9|@]|A|$]]]|V|$]]

MVC 5 / EF 6

perhaps you can do this in the older version?

<ol>
<li>commented out the connection strings in the web / app.config then save</li>
<li>try to create new controller and have VS create a "new" dbcontext item instead of choosing the one you already have</li>
<li>click create</li>
<li>delete new dbcontext class</li>
<li>replace controller dbcontext with yours</li>
<li>uncomment connection strings in web / app.config then save</li>
</ol>

worked for me!

blocks|key|3428780|text|我也收到了同样的错误消息，但这与连接字符串无关。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3428781|这是一个非常罕见的案例，但希望这能帮助到一些人。我的模型名与名称空间名称的一个片段相同。|3428782|例如：|3428783|namespace+blah.blah.Building

public+class+Building|code-block|syntax|javascript|3428784|我重新命名了我的名称空间，修复了所有的使用，然后t4脚手架工作了！|3428785|3428786|她是另一个可能的解决方案。您可能必须首先运行“依赖”模型的脚手架。然后用您的方式处理具有许多依赖项的复杂模型。|3428787|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|S|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|T|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|U|8|@]|9|@]|A|$I|J]]|$1|K|3|L|5|6|7|V|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|W|8|@]|9|@]|A|$]]|$1|N|3|O|5|6|7|X|8|@]|9|@]|A|$]]|$1|P|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|Q|$]]

I had the same error message, but it was nothing to do with the connection string.

It is a very rare case, but hopefully this will help someone. My model name was the same as one of the segments of my namespace name.

For example:

<pre><code>namespace blah.blah.Building

public class Building
</code></pre>

I renamed my namespace and fixed all usages and then the t4 scaffolding worked!

<hr>

Her's another possible solution. You may have to run scaffolding for "dependent" models first. Then work your way up to complicated models that have many dependencies.

blocks|key|4310174|text|在尝试使用脚手架从控制器创建视图时，我遇到了类似的问题。在create对话框中，我只是清除了“数据上下文类”下拉列表，然后脚手架机制使用了很好的措辞。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4310175|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I had a similar issue when trying to create a view from my controller using the scaffolding. In the create view dialog I simply cleared the "Data Context Class" dropdown and then the scaffolding mechanism worded fine.

I'm using RTM version of Windows 8 and VS 2012 Ultimate. I have a MVC4 project using SqlCe 4.0 with a code first entity framework model.

Model is very simple:

<pre><code> public class MyThing
 {
 public int MyThingId { get; set; }

 public int UserId { get; set; }
 public string Title { get; set; }
 public string Address { get; set; }
 public string Description { get; set; }
 public DateTime Date { get; set; }
 }
</code></pre>

When I try to create a new controller with the built in scaffolding too I get the following error:

<blockquote>
 "Unable to retrieve metadata for MyThing"
 
 "Using the same DbCompiledModel to create contexts against different
 types of database servers is not supported. Instead, create a
 separate DbCompiledModel for each type of server being used.
</blockquote>

How do I get scaffolding to work?

MVC4 Scaffolding Add Controller gives error "Unable to retrieve metadata..."

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我正在使用RTM版本的Windows 8和VS 2012终极版。我有一个使用MVC4 SqlCe 4.0的项目，它有一个代码优先实体框架模型。模型非常简单：   public class MyThing    {        public int MyThingId { get; set; }        publ...

问MVC4脚手架添加控制器导致错误“无法检索元数据.”
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问MVC4脚手架添加控制器导致错误“无法检索元数据.”EN