ObjectContext在其构造函数中接受实体连接字符串。实体连接字符串由三部分组成：

• 元数据位置（由EDMX文件生成的XML的映射位置）


• 数据存储提供者


• 数据存储连接字符串（即您想要提供的）

你有几种方式来达到你想要的目的。一般来说，你需要的是连接字符串的两个部分：

  string format =metadata = res：// * / Model。 csdl | res：//*/Model.ssdl | res：//*/Model.msl; provider = System.Data.SqlClient; provider connection string = \{0} \; 
 string connectionString =server = severaddress; database = database1; UserID = test; Password = test1234; 

 var context = ModelContext（String.Format（format，connectionString））; 
 

该格式描述了作为程序集和Sql提供程序中资源的Model.edmx元数据的位置。第二部分是您的连接字符串。

请注意，只有当您的所有数据库具有相同的模式并使用相同的提供者时，这才有效。

I am trying to use the ADO.NET Entity Data Model in a way that I can on the fly change which database I point too. Changing databases may require an entirely new connection string. Some databases are on different servers. So I need the ability to pass my ADO.NET Entity Data Model a custom connection string formated like so 'server=severaddress;database=database1;User ID=test;Password=test1234;'

Edited: My Entity Class implements ObjectContext. The three constructers I can use is the default, pass in connectionString, pass in an EntityConnection. When ever I use the overload constructers I get errors saying it doesn't recognize "server" in the connectionstring.

I need to either instantiate my repository with a custom connection string, or be able to set it before use.

ObjectContext accepts entity connection string in its constructor. Entity connection string consists of three parts:

• Metadata location (location of mapping XMLs produced by EDMX file)
• Data storage provider
• Data store connection string (that is what you want to provide)

You have several ways to achieve what you want. Generally what you need is combine two parts of connection string:

string format = "metadata=res://*/Model.csdl|res://*/Model.ssdl|res://*/Model.msl;provider=System.Data.SqlClient;provider connection string=\"{0}\"";
string connectionString = "server=severaddress;database=database1;UserID=test;Password=test1234;"

var context = ModelContext(String.Format(format, connectionString));

The format describes location of metadata from Model.edmx included as resources in assembly and Sql provider. Second part is your connection string.

Be aware that this will only work if all your databases have same schema and use same provider.