EntityFramework DBContext 类动态控制 数据库连接(支持Oracle，SQL server)

 public class ManagementDBContext : DbContext

    {

        public static string configString = ConfigHelper.GetDatabase;

        public ManagementDBContext() : base(configString)

        {

            Database.SetInitializer<ManagementDBContext>(null);

        }

        /// <summary>

        /// 模型的创建

        /// </summary>

        /// <param name="modelBuilder"></param>

        protected override void OnModelCreating(DbModelBuilder modelBuilder)

        {

            base.OnModelCreating(modelBuilder);

            // 判断使用的数据库动态控制 Schema

            if (ConfigHelper.GetDBType == Enums.Database.Oracle)

            {

                string schema = GetConfiguration("USER ID");

                modelBuilder.HasDefaultSchema(schema);

                modelBuilder.Types().Configure(entity => entity.ToTable(entity.ClrType.Name, schema));

            }

        }

        /// <summary>

        /// 获取配置连接串

        /// </summary>

        /// <param name="str">要取的字符名称</param>

        /// <returns></returns>

        private static string GetConfiguration(string str)

        {

            if (string.IsNullOrEmpty(str)) str = str.ToUpper();

            string con = ConfigHelper.GetConStrings(configString);

            string[] strSplit = con.Split(';');

            Dictionary<string, string> attribList = new Dictionary<string, string>();

            for (int i = 0; i != strSplit.Length; i++)

            {

                string[] attribValue = strSplit[i].Split('=');

                attribList.Add(attribValue[0], attribValue[1]);

            }

            return attribList[str];

        }

        /// <summary>

        /// 导入Excel

        /// </summary>

        public DbSet<ImportExcel> importExcel { get; set; }

    }

 

webconfig 内容

  <connectionStrings>

    <add name="OracleDbContext" providerName="Oracle.ManagedDataAccess.Client" connectionString="User Id=Teest;Password=Test123;Data Source=localhost:1521/orcl" />

    <!--<add name="DefaultConnection" connectionString="Data Source=.;Initial Catalog=databaseLog;Persist Security Info=True;MultipleActiveResultSets=True;Pooling=true;Max Pool Size=512;Min Pool Size=5;Connection Timeout=120" providerName="System.Data.SqlClient" />-->

    <add name="DefaultConnection" connectionString="server=.;database=ManageDB;user id=sa;pwd=sa" providerName="System.Data.SqlClient" />

  </connectionStrings>

 

 

WebConfig 里配置

    <!-- 指定连接数据库 SqlServer/Oracle|0/1-->

    <add key="Database" value="0" />

 

    /// <summary>

    /// 读取配置工具类

    /// </summary>

    public class ConfigHelper

    {

        private static string temp = string.Empty;

        private static string database = ConfigurationManager.AppSettings["Database"].ToString().Trim();

        private static string upload = ConfigurationManager.AppSettings[StringHelper.UPLOAD.ToLower()].ToString().Trim();

        private static string project = AppDomain.CurrentDomain.BaseDirectory.Replace("\\", "/").ToString();

        /// <summary>

        /// 获取链接的数据库

        /// </summary>

        public static string GetDatabase

        {

            get

            {

                if (!string.IsNullOrEmpty(database))

                    return GetConnectionDefaultName(database);

                else return GetConnectionStrings(StringHelper.WEBCONFIG);

            }

        }

        /// <summary>

        /// 读取xml节点名称,返回数据库连接名称

        /// </summary>

        /// <param name="xmlNodeName"></param>

        /// <returns></returns>

        private static string GetConnectionStrings(string fileName)

        {

            string[] array = null;

            XmlDocument doc = new XmlDocument();

            temp = project + fileName;

            if (!FileHelper.FileExists(temp)) return temp;

            doc.Load(temp);

            XmlNodeList nodeList = doc.DocumentElement.ChildNodes;

            if (nodeList.Count > 0)

                foreach (XmlNode node in nodeList)

                {

                    if (node.LocalName.ToLower() != StringHelper.CONNECTIONSTRINGS.ToLower())

                        continue;

                    array = node.InnerXml.Split('>');

                    array = array[0].Replace("\"", "").Split(' ');

                    foreach (var arr in array)

                    {

                        if (arr.ToLower().Contains(StringHelper.NAME.ToLower()))

                        {

                            array = arr.Split('=');

                            break;

                        }

                    }

                }

            return temp = array == null ? null : array[1];

        }

        /// <summary>

        /// 动态获取Web.config 中的链接数据库名称

        /// </summary>

        /// <param name="sqlName"></param>

        /// <returns></returns>

        public static string GetConnectionDefaultName(string sqlName)

        {

            string[] array = null;

            XmlDocument doc = new XmlDocument();

            temp = project + StringHelper.WEBCONFIG;

            if (!FileHelper.FileExists(temp)) return temp;

            doc.Load(temp);

            temp = GetDataBaseName(sqlName);

            XmlNodeList nodeList = doc.DocumentElement.ChildNodes;

            if (nodeList.Count > 0)

            {

                foreach (XmlNode node in nodeList)

                {

                    if (node.LocalName.ToLower() == StringHelper.CONNECTIONSTRINGS.ToLower())

                    {

                        array = node.InnerXml.Split('>');

                        break;

                    }

                }

            }

            if (array.Length > 0)

            {

                for (int i = 0; i < array.Length - 1; i++)

                {

                    if (array[i].ToLower().Contains(temp))

                    {

                        temp = array[i];

                        break;

                    }

                }

            }

            array = temp.Replace("\"", "").Split(' ');

            foreach (var arr in array)

            {

                if (arr.ToLower().Contains(StringHelper.NAME.ToLower()))

                {

                    array = arr.Split('=');

                    break;

                }

            }

            return temp = array == null ? null : array[1];

        }

        /// <summary>

        /// 获取上传文件物理路径

        /// </summary>

        public static string GetPhysicalPath

        {

            get

            {

                if (!string.IsNullOrEmpty(upload))

                    return project + upload;

                else

                    return project + StringHelper.UPLOAD.ToLower();

            }

        }

        /// <summary>

        /// 获取服务器文件路径

        /// </summary>

        public static string GetServicePath

        {

            get

            {

                return FileHelper.IsObliqueBar(GetService) + StringHelper.UPLOAD.ToLower();

            }

        }

        /// <summary>

        /// 获取当前项目地址以及端口号

        /// </summary>

        public static string GetService

        {

            get

            {

                return StringHelper.HTTP.ToLower() + "://" + StringHelper.SERVER_NAME + ":" + StringHelper.SERVER_PORT;

            }

        }

        /// <summary>

        /// 获取链接数据库字符串

        /// </summary>

        /// <param name="conName">数据库链接名称</param>

        /// <returns></returns>

        public static string GetConStrings(string conn)

        {

            if (!string.IsNullOrEmpty(conn))

                return ConfigurationManager.ConnectionStrings[conn].ToString().ToUpper();

            else

                return conn;

        }

        /// <summary>

        /// 获取当前使用的数据库

        /// </summary>

        /// <returns></returns>

        public static string GetDataBaseName(string dbName)

        {

            try

            {

                temp = dbName.ToLower() == StringHelper.ORACLE.ToLower() ? StringHelper.ORACLE.ToLower() :

                    dbName.ToLower() == StringHelper.SQLSERVER.ToLower() ? StringHelper.SQLCLIENT.ToLower() :

                    Convert.ToInt32(dbName.ToLower()) == Convert.ToInt32(Database.SqlServer) ? StringHelper.SQLCLIENT.ToLower() :

                    Convert.ToInt32(dbName.ToLower()) == Convert.ToInt32(Database.Oracle) ? StringHelper.ORACLE.ToLower() : StringHelper.SQLCLIENT.ToLower();

            }

            catch (Exception)

            {

                temp = StringHelper.SQLCLIENT.ToLower();

            }

            return temp;

        }

        /// <summary>

        /// 获取链接数据库类型

        /// </summary>

        public static Database GetDBType

        {

            get

            {

                return GetDatabaseType(database);

            }

        }

        /// <summary>

        /// 以枚举类型返回数据库类型

        /// </summary>

        /// <param name="dbType"></param>

        /// <returns></returns>

        public static Database GetDatabaseType(string dbType)

        {

            try

            {

                return dbType.ToLower() == StringHelper.ORACLE.ToLower() ? Database.Oracle :

                    dbType.ToLower() == StringHelper.SQLSERVER.ToLower() ? Database.SqlServer :

                    Convert.ToInt32(dbType.ToLower()) == Convert.ToInt32(Database.SqlServer) ? Database.SqlServer :

                    Convert.ToInt32(dbType.ToLower()) == Convert.ToInt32(Database.Oracle) ? Database.Oracle : Database.SqlServer;

            }

            catch (Exception)

            {

                return Database.SqlServer;

            }

        }

    }

 特别注意的地方就是实体类

 

作者地址：https://www.cnblogs.com/FGang/p/10593086.html