C#訪問SqlServer的工具類SqlServerHelper

using System;using System.Collections.Generic;using System.Linq;using System.Text;using MySql.Data.MySqlClient;using System.Data;class MySqlHelper:IDisposable    {        private MySqlConnection m_conn = null;        private MySqlTransaction m_trans = null;        private bool m_tran_enabled = false;          public MySqlHelper()        {            m_conn = new MySqlConnection();            m_conn.ConnectionString = "Server=localhost;Port=3301;Uid=sa;Pwd=000";            m_conn.Open();        }          public void BeginTrans()        {            m_trans = m_conn.BeginTransaction();            m_tran_enabled = true;        }          public void Commit()        {            if (m_trans != null && m_tran_enabled)            {                m_tran_enabled = false;                m_trans.Commit();            }        }          public void Rollback()        {            if (m_trans != null && m_tran_enabled)            {                m_tran_enabled = false;                m_trans.Rollback();            }        }          public object QuerySome(string sql,int fieldindex)        {            using (MySqlCommand cmd = new MySqlCommand(sql, m_conn))            {                using (MySqlDataReader sr = cmd.ExecuteReader())                {                    if (sr.Read())                    {                        return sr.GetValue(fieldindex);                    }                }            }            return null;        }          public delegate void FillValues(MySqlDataReader sr);                public void QuerySomes(string sql, FillValues fill)        {            using (MySqlCommand cmd = new MySqlCommand(sql, m_conn))            {                using (MySqlDataReader sr = cmd.ExecuteReader())                {                    fill(sr);                }            }        }          public DataTable Source(string sql)        {            DataTable dt = null;            MySqlCommand cmd = null;            MySqlDataAdapter ad = null;            try            {                lock (dt = new DataTable())                {                    cmd = new MySqlCommand(sql, m_conn);                    ad = new MySqlDataAdapter((MySqlCommand)cmd);                    dt.Clear();                    ad.Fill(dt);                }            }            catch (Exception e)            {                throw e;            }            return dt;        }          public void ExecProc(string proc, params MySqlParameter[] ps)        {            using (MySqlCommand cmd = new MySqlCommand(proc, m_conn))            {                cmd.CommandType = System.Data.CommandType.StoredProcedure;                foreach (MySqlParameter p in ps)                {                    cmd.Parameters.Add(p);                }                cmd.ExecuteNonQuery();            }        }          void IDisposable.Dispose()        {            m_conn.Close();            m_conn.Dispose();            if (m_trans != null)            {                m_trans.Dispose();            }        }    }

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