c# - 通过代码设置实体连接字符串

Question

好的，所以我对切换数据库的实现有了更进一步的了解，我的上下文类中有一个方法。

public string SetupConnections()
{

        //Specify the provider name, server and database.
string providerName = "System.Data.SqlClient";
        string serverName = ".";
        string databaseName = "DBNAME";

        // Initialize the connection string builder for the
        // underlying provider.
        SqlConnectionStringBuilder sqlBuilder =
            new SqlConnectionStringBuilder();

        // Set the properties for the data source.
        sqlBuilder.DataSource = serverName;
        sqlBuilder.InitialCatalog = databaseName;
        sqlBuilder.IntegratedSecurity = false;
        sqlBuilder.UserID = "USERNAME";
        sqlBuilder.Password = "PASS";

        // Build the SqlConnection connection string.
        string providerString = sqlBuilder.ToString();

        // Initialize the EntityConnectionStringBuilder.
        EntityConnectionStringBuilder entityBuilder =
            new EntityConnectionStringBuilder();

        //Set the provider name.
        entityBuilder.Provider = providerName;

        // Set the provider-specific connection string.
        entityBuilder.ProviderConnectionString = providerString;

        // Set the Metadata location.
        entityBuilder.Metadata = @"res://*/Model1.csdl|res://*/Model1.ssdl|res://*/Model1.msl";
        Console.WriteLine(entityBuilder.ToString());

        using (EntityConnection conn =
            new EntityConnection(entityBuilder.ToString()))
        {
            conn.Open();
            Console.WriteLine("Just testing the connection.");
            conn.Close();
        }
        return sqlBuilder.ToString();
    }

但是当我运行该应用程序时，它说底层提供程序无法为用户打开，我是否添加了正确的用户名和密码？出于安全原因，obv 伪装了我的真实密码。

这是我的原始连接字符串。我在 technet 上关注这个例子

https://learn.microsoft.com/en-us/dotnet/framework/data/adonet/ef/how-to-build-an-entityconnection-connection-string

是的，我没有那个例子是集成的 security = true 但我不想使用我想使用的用户名和密码。

 <add name="SMBASchedulerEntities" connectionString="metadata=res://*/Model1.csdl|res://*/Model1.ssdl|res://*/Model1.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=sourcenet;initial catalog=COASTALCAROLINAPODIATRY;User ID=scheduler;Password=Pass;MultipleActiveResultSets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" />

我也遇到了这个错误，因为我正在使用 DB First

: The context is being used in Code First mode with code that was generated from an EDMX file for either Database First or Model First development. This will not work correctly. To fix this problem do not remove the line of code that throws this exception. If you wish to use Database First or Model First, then make sure that the Entity Framework connection string is included in the app.config or web.config of the start-up project. If you are creating your own DbConnection, then make sure that it is an EntityConnection and not some other type of DbConnection, and that you pass it to one of the base DbContext constructors that take a DbConnection. To learn more about Code First, Database First, and Model First see the Entity Framework documentation here: http://go.microsoft.com/fwlink/?LinkId=394715

我没有得到任何数据，或者我将我的实体对象更改为如下。

    public SMBASchedulerEntities(string sConnectionString)
        : base(sConnectionString)
    {

    }

Answer 1

您正在为 entityBuilder.Provider 提供“System.Data.SqlClient”，但据我所知，它应该是“System.Data.EntityClient”以使用实体生成器创建连接字符串。