打造 通用的 支持多数据库 操作的 DBHelper

闲来无事，写一个通用的直持多数据库的DBHelper，支持单连接批量执行SQL

因为用了TransactionScope所以请引用System.TransactionScope.dll

代码尚未测试，请不要在生产环境中使用，后续会用测试好的代码替换，并会持续支持，欢迎大家一起学习

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废话不多说直接上代码

using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Utility
{
    internal class DbObject
    {
        /// <summary>
        /// 脚本
        /// </summary>
        internal string CommandText
        {
            get;set;
        }

        /// <summary>
        /// 脚本参数集
        /// </summary>
        internal IList<IDbDataParameter> DbParameters
        {
            get;
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Transactions;

namespace Utility
{
    internal class DBHelper<T> where T : class, IDbConnection, new()
    {

        /// <summary>
        /// 装载参数
        /// </summary>
        /// <param name="command"></param>
        /// <param name="parameters"></param>
        private void PrepareDbParameters(IDbCommand command, IDbDataParameter[] parameters)
        {
            if (Equals(command, null))
                throw new Exception("Command对象不能为空");

            foreach (var item in parameters)
                command.Parameters.Add(item);
        }

        private void PrepareDbParameters(IDbCommand command, IList<IDbDataParameter> parameters)
        {
            if (Equals(command, null))
                throw new Exception("Command对象不能为空");

            foreach (var item in parameters)
                command.Parameters.Add(item);
        }

        /// <summary>
        /// 执行查询
        /// </summary>
        /// <typeparam name="U"></typeparam>
        /// <param name="connectionString">连接字符串</param>
        /// <param name="commandText">查询语句</param>
        /// <param name="parameters">查询参数</param>
        /// <returns>数据集</returns>
        internal DataSet ExecuteQuery<U>(string connectionString, CommandType commandType, string commandText,
            IDbDataParameter[] parameters)
            where U : class, IDbDataAdapter, new()
        {
            using (IDbConnection conn = new T())
            {
                conn.ConnectionString = connectionString;
                IDbCommand command = conn.CreateCommand();
                command.CommandType = commandType;
                command.CommandText = commandText;
                this.PrepareDbParameters(command, parameters);
                using (var ds = new DataSet())
                {
                    IDbDataAdapter adapter = new U();
                    adapter.SelectCommand = command;
                    adapter.Fill(ds);
                    return ds;
                }
            }
        }

        /// <summary>
        /// 执行查询
        /// </summary>
        /// <param name="connectionString">连接字符串</param>
        /// <param name="commandType">脚本类型</param>
        /// <param name="commandText">执行的脚本</param>
        /// <param name="parameters">执行参数</param>
        /// <param name="behavior">查询结果行为</param>
        /// <returns></returns>
        internal IDataReader ExecuteReader(string connectionString, CommandType commandType, string commandText,
            IDbDataParameter[] parameters, CommandBehavior behavior)
        {
            using (IDbConnection conn = new T())
            {
                conn.ConnectionString = connectionString;
                IDbCommand command = conn.CreateCommand();
                command.CommandType = commandType;
                command.CommandText = commandText;
                this.PrepareDbParameters(command, parameters);
                if (conn.State == ConnectionState.Broken)
                    conn.Close();

                if (conn.State != ConnectionState.Open)
                    conn.Open();

                using (var reader = command.ExecuteReader(behavior))
                {
                    return reader;
                }
            }
        }

        /// <summary>
        /// 执行SQL
        /// </summary>
        /// <param name="connectionString"></param>
        /// <param name="commandType"></param>
        /// <param name="commandText"></param>
        /// <param name="parameters"></param>
        internal U ExecuteScalar<U>(string connectionString, CommandType commandType, string commandText,
            IDbDataParameter[] parameters)
            where U : struct
        {
            using (IDbConnection conn = new T())
            {
                conn.ConnectionString = connectionString;
                IDbCommand command = conn.CreateCommand();
                command.CommandType = commandType;
                command.CommandText = commandText;
                this.PrepareDbParameters(command, parameters);
                if (conn.State == ConnectionState.Broken)
                    conn.Close();

                if (conn.State != ConnectionState.Open)
                    conn.Open();

                var result = (U)command.ExecuteScalar();
                conn.Close();
                return result;
            }
        }

        /// <summary>
        /// 批量执行SQL
        /// </summary>
        /// <param name="connectionString"></param>
        /// <param name="commandType"></param>
        /// <param name="commandText"></param>
        /// <param name="parameters"></param>
        /// <param name="behavior"></param>
        /// <returns></returns>
        internal IList<U> ExecuteScalarBatch<U>(string connectionString, CommandType commandType, IList<DbObject> dbObjects)
            where U : struct
        {
            using (IDbConnection conn = new T())
            {
                using (TransactionScope trans = new TransactionScope())
                {
                    IList<U> list = new List<U>();
                    try
                    {
                        for (var i = 0; i < dbObjects.Count; i++)
                        {
                            var curDbObj = dbObjects[i];
                            conn.ConnectionString = connectionString;
                            IDbCommand command = conn.CreateCommand();
                            command.CommandType = commandType;
                            command.CommandText = curDbObj.CommandText;
                            this.PrepareDbParameters(command, curDbObj.DbParameters.ToArray());
                            if (conn.State == ConnectionState.Broken)
                                conn.Close();

                            if (conn.State != ConnectionState.Open)
                                conn.Open();

                            var result = (U)command.ExecuteScalar();
                            list.Add(result);
                            trans.Complete();
                        }
                    }
                    catch (Exception ex)
                    {                        
                        throw ex;
                    }

                    return list;
                }
            }
        }

        /// <summary>
        /// 执行SQL
        /// </summary>
        /// <param name="connectionString"></param>
        /// <param name="commandType"></param>
        /// <param name="commandText"></param>
        /// <param name="parameters"></param>
        /// <param name="behavior"></param>
        /// <returns></returns>
        internal int ExecuteNoneQuery(string connectionString, CommandType commandType, string commandText,
            IDbDataParameter[] parameters, CommandBehavior behavior)
        {
            using (IDbConnection conn = new T())
            {
                conn.ConnectionString = connectionString;
                IDbCommand command = conn.CreateCommand();
                command.CommandType = commandType;
                command.CommandText = commandText;
                this.PrepareDbParameters(command, parameters);
                if (conn.State == ConnectionState.Broken)
                    conn.Close();

                if (conn.State != ConnectionState.Open)
                    conn.Open();

                int affectCount = command.ExecuteNonQuery();
                return affectCount;
            }
        }

        /// <summary>
        /// 批量执行SQL
        /// </summary>
        /// <param name="connectionString"></param>
        /// <param name="commandType"></param>
        /// <param name="commandText"></param>
        /// <param name="parameters"></param>
        /// <param name="behavior"></param>
        /// <returns></returns>
        internal IList<int> ExecuteNoneQueryBatch<U>(string connectionString, CommandType commandType, IList<DbObject> dbObjects)
        {
            using (IDbConnection conn = new T())
            {
                using (TransactionScope trans = new TransactionScope())
                {
                    IList<int> list = new List<int>();
                    try
                    {
                        for (var i = 0; i < dbObjects.Count; i++)
                        {
                            var curDbObj = dbObjects[i];
                            conn.ConnectionString = connectionString;
                            IDbCommand command = conn.CreateCommand();
                            command.CommandType = commandType;
                            command.CommandText = curDbObj.CommandText;
                            this.PrepareDbParameters(command, curDbObj.DbParameters.ToArray());
                            if (conn.State == ConnectionState.Broken)
                                conn.Close();

                            if (conn.State != ConnectionState.Open)
                                conn.Open();

                            var result = command.ExecuteNonQuery();
                            list.Add(result);
                            trans.Complete();
                        }
                    }
                    catch (Exception ex)
                    {
                        throw ex;
                    }

                    return list;
                }
            }
        }

    }
}

 后续会放出基于该类的SqlHelper