EF6的DbContext动态连接字符串 [英] EF6 DBContext Dynamic Connection String

问题描述

 公共部分类ProcessContext：的DbContext
{
    静态ProcessContext（）
    {
        Database.SetInitializer＆LT; ProcessContext＆GT;（NULL）;
    }    公共ProcessContext（）
        ：基地（NAME = ProcessCS）//从配置文件来自
    {
    }    --DBSets
    保护覆盖无效OnModelCreating（DbModelBuilder模型构建器）
    {
        -  code
    }
}
 

这是一个多Tenent DB，我们有3个不同的DB。集中DB是在共同的位置和将不被改变。这是的DB细节其余部分将被保存。我需要创造一个细节将从这种集中DB中传来的连接字符串@运行。可有一个人请让我知道如何去了解呢？

我试着用下面的code，但它不工作。该方法将在这里被称为

 公共ProcessContext（）
    ：基地（nameOrConnectionString：的ConnectionString（））
{
}私人静态字符串的ConnectionString（）
{
    SqlConnectionStringBuilder sqlBuilder =新SqlConnectionStringBuilder（）;
    sqlBuilder.DataSource =XXX;
    sqlBuilder.InitialCatalog =YYY;
    sqlBuilder.PersistSecurityInfo = TRUE;
    sqlBuilder.IntegratedSecurity = TRUE;
    sqlBuilder.MultipleActiveResultSets = TRUE;    EntityConnectionStringBuilder entityBuilder =新EntityConnectionStringBuilder（）;
    entityBuilder.ProviderConnectionString = sqlBuilder.ToString（）;
    entityBuilder.Metadata =RES：// * /;
    entityBuilder.Provider =System.Data.SqlClient的;    返回entityBuilder.ToString（）;
}
 

解决方案

有关SQL Server连接，覆盖实体容器类：（EF6中的作品，SQL Server 2012的前preSS，VS2013）

 公共部分类PxxxxEntities
{
    私人PxxxxEntities（字符串的connectionString）
        ：基地（的connectionString）
    {
    }    公共静态PxxxxEntities ConnectToSqlServer（字符串主机，串目录，用户字符串，字符串传递，布尔winAuth）
    {
        SqlConnectionStringBuilder sqlBuilder =新SqlConnectionStringBuilder
        {
            数据源=主机，
            InitialCatalog =目录，
            PersistSecurityInfo = TRUE，
            IntegratedSecurity = winAuth，
            MultipleActiveResultSets = TRUE，            用户名=用户，
            密码=传球，
        };        //在MyDbEntities中的.config假定的connectionString名
        VAR entityConnectionStringBuilder =新EntityConnectionStringBuilder
        {
            供应商=System.Data.SqlClient的
            ProviderConnectionString = sqlBuilder.ConnectionString，
            元数据=RES：//*/DbModel.csdl |高分辨率：//*/DbModel.ssd​​l |高分辨率：//*/DbModel.msl
        };        返回新PxxxxEntities（entityConnectionStringBuilder.ConnectionString）;
    }
}
 

public partial class ProcessContext : DbContext
{
    static ProcessContext()
    {
        Database.SetInitializer<ProcessContext>(null);
    }

    public ProcessContext()
        : base("Name=ProcessCS") //Comes from Config File
    {
    }

    --DBSets 
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
       --Code
    }
}

This is a Multi Tenent DB where we have 3 Different DB's. Centralized DB is in common location and would not be changed. This is where rest of the DB details will be stored. I need to create the Connection string @ runtime where the details will be coming from this centralized DB. Can some one please let me know how to go about it?

I tried with the following code, but it is not working. This Method will be called here

public ProcessContext()
    : base(nameOrConnectionString: ConnectionString())
{
}

private static string ConnectionString()
{
    SqlConnectionStringBuilder sqlBuilder = new SqlConnectionStringBuilder();
    sqlBuilder.DataSource = "XXX";
    sqlBuilder.InitialCatalog = "YYY";
    sqlBuilder.PersistSecurityInfo = true;
    sqlBuilder.IntegratedSecurity = true;
    sqlBuilder.MultipleActiveResultSets = true;

    EntityConnectionStringBuilder entityBuilder = new EntityConnectionStringBuilder();
    entityBuilder.ProviderConnectionString = sqlBuilder.ToString();
    entityBuilder.Metadata = "res://*/";
    entityBuilder.Provider = "System.Data.SqlClient";

    return entityBuilder.ToString();
}

解决方案

For SQL Server connection, override the entity container class: (works in EF6, SQL server 2012 express, VS2013)

public partial class PxxxxEntities
{
    private PxxxxEntities(string connectionString)
        : base(connectionString)
    {
    }

    public static PxxxxEntities ConnectToSqlServer(string host, string catalog, string user, string pass, bool winAuth)
    {
        SqlConnectionStringBuilder sqlBuilder = new SqlConnectionStringBuilder
        {
            DataSource = host,
            InitialCatalog = catalog,
            PersistSecurityInfo = true,
            IntegratedSecurity = winAuth,
            MultipleActiveResultSets = true,

            UserID = user,
            Password = pass,
        };

        // assumes a connectionString name in .config of MyDbEntities
        var entityConnectionStringBuilder = new EntityConnectionStringBuilder
        {
            Provider = "System.Data.SqlClient",
            ProviderConnectionString = sqlBuilder.ConnectionString,
            Metadata = "res://*/DbModel.csdl|res://*/DbModel.ssdl|res://*/DbModel.msl",
        };

        return new PxxxxEntities(entityConnectionStringBuilder.ConnectionString);
    }
}

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