ADO.NET Entity Framework “Unable to load the specified metadata resource”解决方法

当我使用下边代码打开Entity时。程序报 “Unable to load the specified metadata resource”错。

 string con = "name = NorthwindEntities";
            using (EntityConnection econn = new EntityConnection(esb.ConnectionString))
            {
                econn.Open();
            }

错误是因为Web.Config连接节点中connectionString引起。请看系统的Web.Config连接节点。

<configuration>
  <connectionStrings>
    <add name="NorthwindEntities" 
         connectionString="metadata=res://*/NothWind.csdl|res://*/NothWind.ssdl|res://*/NothWind.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=.;Initial Catalog=Northwind;User ID=sa;Password=123;MultipleActiveResultSets=True&quot;" 
         providerName="System.Data.EntityClient" />
  </connectionStrings>
</configuration>

将Metadata中"*"换成.edmx所在程序集的名称即可。如下。

<configuration>
  <connectionStrings>
    <add name="NorthwindEntities" 
         connectionString="metadata=res://EFModel/NothWind.csdl|res://EFModel/NothWind.ssdl|res://EFModel/NothWind.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=.;Initial Catalog=Northwind;User ID=sa;Password=123;MultipleActiveResultSets=True&quot;" 
         providerName="System.Data.EntityClient" />
  </connectionStrings>
</configuration>