兩個實體類比較，記錄前后的數據變化，精確到每列的值

不是通用的方法，只是提供一個思路。

實體類：

    /// <summary>
    /// 體例數據實體類
    /// </summary>
    public class RulesLayout
    {
        /// <summary>
        /// 體例元數據行業代碼
        /// </summary>
        public string hydm { get; set; }
        /// <summary>
        /// 體例元數據行業名稱
        /// </summary>
        public string hymc { get; set; }
        /// <summary>
        /// 體例元數據主體代碼
        /// </summary>
        public string ztdm { get; set; }
        /// <summary>
        /// 體例元數據主體名稱
        /// </summary>
        public string ztmc { get; set; }
        /// <summary>
        /// 體例元數據結構代碼
        /// </summary>
        public string jgdm { get; set; }
        /// <summary>
        /// 體例元數據結構名稱
        /// </summary>
        public string jgmc { get; set; }
        /// <summary>
        /// 體例元數據結構名稱同義詞
        /// </summary>
        public string jgmctyc { get; set; }
        /// <summary>
        /// 體例元數據代碼
        /// </summary>
        public string ysjdm { get; set; }
        /// <summary>
        /// 體例元數據名稱
        /// </summary>
        public string ysjmc { get; set; }
        /// <summary>
        /// 體例元數據名稱同義詞
        /// </summary>
        public string ysjmctyc { get; set; }
        /// <summary>
        /// 屬性
        /// </summary>
        public string sx { get; set; }
        /// <summary>
        /// 狀態
        /// </summary>
        public string zt { get; set; }
        
    }

數據庫操作類

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.OracleClient;
using System.Data.OleDb;
using System.Windows.Forms;
using System.Collections;
using System.Data;
namespace DbProvider
{

    /// <summary>
    /// 體例數據操作類
    /// </summary>
    public static class StyleData
    {
       public static string constr = " 數據庫連接字符串";
       static OracleConnection con=null;
       static OracleTransaction tran = null;
       static OracleCommand cmd = null;
        /// <summary>
        /// 執行一個sql語句，返回第一個值
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static object GetOneValue(string sql)
        {
            using (con = new OracleConnection(constr))
            {
                con.Open();
                 cmd = new OracleCommand(sql, con);
                return cmd.ExecuteOracleScalar();
            }
        }
        /// <summary>
        /// 執行一個sql語句
        /// </summary>
        /// <param name="sql"></param>
        public static int ExecSql(string sql)
        {
            using (con= new OracleConnection(constr))
            {
                con.Open();
                cmd = new OracleCommand(sql, con);
                return cmd.ExecuteNonQuery();
            }
        }

        /// <summary>
        /// 執行sql語句獲取datareader,讀取完畢后，必須關閉datareader
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static OracleDataReader GetReader(string sql)
        {
            OracleDataReader dr = null;
            con = new OracleConnection(constr);
            con.Open();
            OracleCommand cmd= new OracleCommand(sql, con);
            dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
            return dr;
        
        }
        /// <summary>
        /// 在事務中執行多個sql語句
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static bool ExeclSqlList(List<string>sql)
        {
            try
            {
                con = new OracleConnection(constr);
                tran = cmd.Transaction;
                con.Open();
                con.BeginTransaction();
                foreach (string s in sql)
                {
                    cmd = new OracleCommand(s, con, tran);
                    cmd.ExecuteNonQuery();
                }
                tran.Commit();
                tran.Dispose();
                return true;
            }
            catch
            {
                tran.Rollback();
                tran.Dispose();
                return false;
            }
        }

       
    }
}

　　業務實現類：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Collections;
using System.Data.OleDb;
using System.Data.OracleClient;
using System.Windows.Forms;
using System.Drawing;
namespace DbProvider
{
    /// <summary>
    ///體例元數據業務輔助類
    /// </summary>
    public class StyleDataAssist
    {
        /// <summary>
        /// 創建數據庫輔助表，並把表名添加到t_system_data記錄
        /// </summary>
        /// <returns></returns>
        public ArrayList CreateSubsidiaryTable()
        {
            ArrayList tbl = new ArrayList();
            string str = StyleData.GetOneValue("select max(num) from t_system_data").ToString();
            int i = 0;
            if (String.IsNullOrEmpty(str))
            {
                i = 1;
            }
            else
            {
                i += 1;
            }
            string vocation = "t_rvl_style_vocation" + i.ToString();
            string main = "t_rvl_style_main" + i.ToString();
            string frame = "t_rvl_style_frame" + i.ToString();
            string metadata = "t_rvl_style_metadata" + i.ToString();
            //創建輔助表
            string sqlvoc = "create table " + vocation + " as select * from t_rvl_style_vocation where 1=1";
            string sqlmain = "create table " + main + " as select * from t_rvl_style_main where 1=1";
            string sqlfrm = "create table " + frame + " as select * from t_rvl_style_frame where 1=1 ";
            string sqldat = "create table " + metadata + "  as select * from t_rvl_style_metadata where 1=1 ";
            //將輔助表的信息插入到t_system_data表記錄
            string names = vocation + "," + main + "," + frame + "," + metadata;
            string insert = "insert into t_system_data(tablenames,chagetime,num) values('" + names + "','" + DateTime.Now.ToLongDateString() + "'," + i + ")";
            List<string> sql = new List<string>();
            sql.Add(sqlvoc);
            sql.Add(sqlmain);
            sql.Add(sqlfrm);
            sql.Add(sqldat);
            if (StyleData.ExeclSqlList(sql))
            {
                tbl.Add(vocation);
                tbl.Add(main);
                tbl.Add(frame);
                tbl.Add(metadata);
            }
            return tbl;
        }
        /// <summary>
        /// 從數據庫中獲取體例元數據
        /// </summary>
        /// <param name="where"></param>
        /// <returns></returns>
        public  List<RulesLayout> GetStyleData(string where)
        {
            List<RulesLayout> List = new List<RulesLayout>();
            RulesLayout rule = null;
            StringBuilder sql = new StringBuilder();
            sql.Append("select vc.vocation_code as 行業代碼,vc.vocation_name as 行業名稱,");
            sql.Append("  main.code as 主體代碼,main.caption as 主體名稱, ");
            sql.Append(" frame.frame_code as 結構代碼, frame.frame_name as 結構名稱,  frame.frame_name_synonyms as 結構名稱同義詞, ");
            sql.Append("data.code as 元數據代碼, data.caption as 元數據名稱, data.synonyms as 元數據名稱同義詞,");
            sql.Append("    data.attribute as 屬性 ");
            sql.Append("  from t_rvl_style_vocation  vc");
            sql.Append(" inner join t_rvl_style_main main on vc.vocation_code = main.vocation_code ");
            sql.Append("  inner join t_rvl_style_frame frame on main.id = frame.main_id ");
            sql.Append(" inner join t_rvl_style_metadata data on frame.id = data.frame_id where 1=1 ");
            sql.Append(where);
            sql.Append("  order by vc.vocation_code ");
            try
            {
                OracleDataReader dr = StyleData.GetReader(sql.ToString());
                while (dr.Read())
                {
                    rule = new RulesLayout();
                    rule.hydm = dr["行業代碼"].ToString();
                    rule.hymc = dr["行業名稱"].ToString();
                    rule.ztdm = dr["主體代碼"].ToString();
                    rule.ztmc = dr["主體名稱"].ToString();
                    rule.jgdm = dr["結構代碼"].ToString();
                    rule.jgmc = dr["結構名稱"].ToString();
                    rule.jgmctyc = dr["結構名稱同義詞"].ToString();
                    rule.ysjdm = dr["元數據代碼"].ToString();
                    rule.ysjmc = dr["元數據名稱"].ToString();
                    rule.ysjmctyc = dr["元數據名稱同義詞"].ToString();
                    rule.sx = dr["屬性"].ToString();
 
                    List.Add(rule);
                }
                dr.Close();
                dr.Dispose();
                return List;
            }
            catch (Exception ex)
            {
                return null;
            }
        }
        /// <summary>
        /// 讀取excel數據
        /// </summary>
        /// <param name="filename"></param>
        /// <returns></returns>
        public List<RulesLayout> ReadExcel(string filename,string where)
        {
            List<RulesLayout> List = new List<RulesLayout>();
            RulesLayout rule = null;
            string strCon = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + filename + ";Extended Properties='Excel 8.0;IMEX=1'";
            OleDbConnection Conn = new OleDbConnection(strCon);
            string strCom = "SELECT distinct  * FROM [屬性$]  where 1=1 "+where;
            Conn.Open();
            OleDbCommand cmd = null;
            string refmsg = "";
            bool result = CheckExcel(Conn, cmd, ref refmsg);
            if (1 == 1)
            {
                cmd = new OleDbCommand(strCom, Conn);
                OleDbDataReader dr;
                dr = cmd.ExecuteReader();
                while (dr.Read())
                {
                    rule = new RulesLayout();
                    rule.hydm = dr["體例元數據行業代碼"].ToString();
                    rule.hymc = dr["體例元數據行業名稱"].ToString();
                    rule.ztdm = dr["體例元數據主體代碼"].ToString();
                    rule.ztmc = dr["體例元數據主體名稱"].ToString();
                    rule.jgdm = dr["體例元數據結構代碼"].ToString();
                    rule.jgmc = dr["體例元數據結構名稱"].ToString();
                    rule.jgmctyc = dr["體例元數據結構名稱同義詞"].ToString();
                    rule.ysjdm =dr["體例元數據代碼"].ToString();
                    rule.ysjmc =dr["體例元數據名稱"].ToString();
                    rule.ysjmctyc =dr["體例元數據名稱同義詞"].ToString();
                    rule.sx = dr["屬性"].ToString();
                    List.Add(rule);
                }
                Conn.Close();
                Conn.Dispose();
                return List;
            }
            else
            {
                Conn.Close();
                Conn.Dispose();
                return null;
            }

        }
        /// <summary>
        /// 檢查excel數據的准確性
        /// </summary>
        /// <param name="con"></param>
        /// <param name="cmd"></param>
        /// <param name="msg"></param>
        /// <returns></returns>
        private bool CheckExcel(OleDbConnection con, OleDbCommand cmd, ref string msg)
        {
            StringBuilder sql = new StringBuilder();
            StringBuilder Msg = new StringBuilder();
            sql.Append("SELECT   * FROM [屬性$] where 體例元數據行業代碼<>'' ");
            sql.Append("or 體例元數據行業名稱<>'' or 體例元數據主體代碼<>''  ");
            sql.Append("or 體例元數據主體名稱<>'' or 體例元數據結構代碼<>'' or 體例元數據結構名稱<>''");
            cmd = new OleDbCommand(sql.ToString(), con);
            OleDbDataReader dr;
            dr = cmd.ExecuteReader();
            Msg.Append("excel 數據錯誤:");
            if (dr.Read())
            {

                Msg.Append("體例元數據行業代碼:" + dr["體例元數據行業代碼"].ToString());
                Msg.Append("體例元數據行業名稱:" + dr["體例元數據行業名稱"].ToString());
                Msg.Append("體例元數據主體代碼:" + dr["體例元數據主體代碼"].ToString());
                Msg.Append("體例元數據主體名稱:" + dr["體例元數據主體名稱"].ToString());
                Msg.Append("體例元數據結構代碼:" + dr["體例元數據結構代碼"].ToString());
                Msg.Append("體例元數據結構名稱:" + dr["體例元數據結構名稱"].ToString());
                Msg.Append("\r\n");
            }

            if (Msg.ToString() != "excel 數據錯誤:")
            {
                msg = Msg.ToString();
                return false;

            }
            else
            {
                msg = "";
                return true;
            }
        }

        /// <summary>
        /// 比較excel的數據和數據庫的數據,獲取差異數據
        /// </summary>
        /// <param name="file">來自文件的數據</param>
        /// <param name="data">來自數據庫原來的數據</param>

        /// <returns></returns>
        public List<RulesLayout> CompareDataList(List<RulesLayout> file, List<RulesLayout> data)
        {
            List<RulesLayout> Comp = new List<RulesLayout>();
            // List<RulesLayout> datacopy = data;
            RulesLayout rule ;
            #region 沒有發生改變的
            Comp = GetSameDataInFile(file, data);
            List<RulesLayout> sameindata = GetSameDataInData(file, data);
            #endregion
            // 從file,data里面移除2者相同的數據，減少下方的遍歷次數
            foreach (RulesLayout r in Comp)
            {
                file.Remove(r);
            }         
            foreach (RulesLayout r in sameindata)
            {
                data.Remove(r);
            }

            #region 更改了的
            int fnum = file.Count;
       

            for (int f = 0; f < fnum; f++)
            {
                bool isAdd = true;//是否是新增數據
                RulesLayout fuleRule = file[f];
                for (int d = 0; d < data.Count; d++)
                {
                    RulesLayout dataRule = data[d];

                    bool isquery = (fuleRule.hydm == dataRule.hydm) && (fuleRule.ztdm == dataRule.ztdm)
                                  && (fuleRule.jgdm == dataRule.jgdm) && (fuleRule.ysjdm == dataRule.ysjdm);
                    if (isquery)
                    {
                        rule = CompareRule(fuleRule, dataRule);
                        Comp.Add(rule);
                        //發生更改了的數據在原數據庫實體類集合里面刪除
                        data.RemoveAt(d);
                        isAdd = false;
                    }
                }
                if (isAdd)
                {
                    fuleRule.zt = "新增";
                    Comp.Add(fuleRule);

                }

            }
            #endregion

            #region  獲取刪除的數據
            var deletedata = data;

            foreach (RulesLayout r in deletedata)
            {
                r.zt = "刪除";
                Comp.Add(r);

            }
            #endregion
            return Comp.OrderBy(m => m.zt).ToList();
        }

        /// <summary>
        /// 獲取修改過的字段信息
        /// </summary>
        /// <param name="file"></param>
        /// <param name="data"></param>
        /// <returns></returns>
      private RulesLayout CompareRule(RulesLayout file, RulesLayout data)
        {
            StringBuilder gg = new StringBuilder();
            #region 比較2個實體類的每個字段，如果不同，就記錄下字段名字
            //並最后更新下來自文本的實體類的狀態屬性
            if (file.hydm != data.hydm)
            {
               // gg.Append("行業代碼,");
                gg.Append("hydm,");
            }
            if (file.hymc != data.hymc)
            {
               // gg.Append("行業名稱,");
                gg.Append("hymc,");
            }
            if (file.ztdm != data.ztdm)
            {
                //gg.Append("主體代碼,");   
                gg.Append("ztdm,");   
            }
            if (file.ztmc != data.ztmc)
            {
                //gg.Append("主體名稱,"); 
                gg.Append("ztmc,"); 
            }
            if (file.jgdm != data.jgdm)
            {
                //gg.Append("結構代碼,");
                gg.Append("jgdm,");
            }
            if (file.jgmc != data.jgmc)
            {
               // gg.Append("結構名稱,");   
                gg.Append("jgmc,");   
            }
            if (file.jgmctyc != data.jgmctyc)
            {
                //gg.Append("結構名稱同義詞,");  
                gg.Append("jgmctyc,");  
            }
            if (file.ysjdm != data.ysjdm)
            {
                //gg.Append("元數據代碼,"); 
                gg.Append("ysjdm,"); 
            }
            if (file.ysjmc != data.ysjmc)
            {
                //gg.Append("元數據名稱,");       
                gg.Append("ysjmc,");  
            }
            if (file.ysjmctyc != data.ysjmctyc)
            {
              //  gg.Append("元數據名稱同義詞,");
                gg.Append("ysjmctyc,");
            }
            if (file.sx != data.sx)
            {
               // gg.Append("屬性,");      
                gg.Append("sx,");      
            }
            #endregion
            file.zt = gg.Append("修改").ToString();
        
            return file;

        }
        /// <summary>
        /// 獲取File相同的數據
        /// </summary>
        /// <param name="File"></param>
        /// <param name="Data"></param>
        /// <returns></returns>
       private List<RulesLayout> GetSameDataInFile(List<RulesLayout> File, List<RulesLayout> Data)
        {
            var same = from f in File join d in Data
                           on new
                           {
                               hydm= f.hydm,
                               hymc=f.hymc,
                               ztdm=f.ztdm,
                               ztmc=f.ztmc,
                               jgdm=f.jgdm,
                               jgmc=f.jgmc,
                               gjmctyc=f.jgmctyc,
                               ysjdm=f.ysjdm,
                               ysjmc=f.ysjmc,
                               ysjmctyc=f.ysjmctyc, 
                              sx=f.sx                             
                           }                         
                          equals
                           new
                           {
                               hydm = d.hydm,
                               hymc = d.hymc,
                               ztdm = d.ztdm,
                               ztmc = d.ztmc,
                               jgdm = d.jgdm,
                               jgmc = d.jgmc,
                               gjmctyc = d.jgmctyc,
                               ysjdm = d.ysjdm,
                               ysjmc = d.ysjmc,
                               ysjmctyc = d.ysjmctyc,
                               sx = d.sx
                           }                       
                       select f;
            return same.ToList();
        }

       /// <summary>
       /// 獲取File相同的數據
       /// </summary>
       /// <param name="File"></param>
       /// <param name="Data"></param>
       /// <returns></returns>
       private List<RulesLayout> GetSameDataInData(List<RulesLayout> File, List<RulesLayout> Data)
       {
           var same = from f in File
                      join d in Data
                          on new
                          {
                              hydm = f.hydm,
                              hymc = f.hymc,
                              ztdm = f.ztdm,
                              ztmc = f.ztmc,
                              jgdm = f.jgdm,
                              jgmc = f.jgmc,
                              gjmctyc = f.jgmctyc,
                              ysjdm = f.ysjdm,
                              ysjmc = f.ysjmc,
                              ysjmctyc = f.ysjmctyc,
                              sx = f.sx
                          }
                          equals
                          new
                          {
                              hydm = d.hydm,
                              hymc = d.hymc,
                              ztdm = d.ztdm,
                              ztmc = d.ztmc,
                              jgdm = d.jgdm,
                              jgmc = d.jgmc,
                              gjmctyc = d.jgmctyc,
                              ysjdm = d.ysjdm,
                              ysjmc = d.ysjmc,
                              ysjmctyc = d.ysjmctyc,
                              sx = d.sx
                          }
                      select d;
           return same.ToList();
       }
       /// <summary>
       /// datagridview變色並且發生改變的數據在ToolTipText中顯示出改變前的
       /// </summary>
       public void DataGridViewAddColor(DataGridView dataGridView1)
       {
           string contr = StyleData.constr;
           using (OracleConnection con = new OracleConnection(contr))
           {
               con.Open();
               OracleCommand cmd = null;
               int count = dataGridView1.RowCount;
               #region 遍歷改色賦值
               for (int i = 0; i < count; i++)
               {
                   if (dataGridView1.Rows[i].Cells["zt"].Value != null)
                   {

                       string statue = dataGridView1.Rows[i].Cells["zt"].Value.ToString();
        
                       if (statue == "新增")
                       {
                           dataGridView1.Rows[i].DefaultCellStyle.BackColor = Color.Yellow;
                   
                       }
                       else if (statue == "刪除")
                       {
                           dataGridView1.Rows[i].DefaultCellStyle.BackColor = Color.Red;
                       }
                       else
                       {
                           string[] cells = statue.Split(',');
                           for (int a = 0; a < cells.Length - 1; a++)
                           {                
                               dataGridView1.Rows[i].Cells[cells[a]].Style.BackColor = Color.Green;
                               cmd = new OracleCommand(GetAlterSql(cells[a]), con);
                               cmd.Parameters.Add(":hydm", OracleType.NVarChar);
                               cmd.Parameters.Add(":ztdm", OracleType.NVarChar);
                               cmd.Parameters.Add(":jgdm", OracleType.NVarChar);
                               cmd.Parameters.Add(":ysjdm", OracleType.NVarChar);
                               cmd.Parameters[":hydm"].Value=dataGridView1.Rows[i].Cells["hydm"].Value;
                               cmd.Parameters[":ztdm"].Value = dataGridView1.Rows[i].Cells["ztdm"].Value;
                               cmd.Parameters[":jgdm"].Value = dataGridView1.Rows[i].Cells["jgdm"].Value;
                               cmd.Parameters[":ysjdm"].Value = dataGridView1.Rows[i].Cells["ysjdm"].Value;

                               dataGridView1.Rows[i].Cells[cells[a]].ToolTipText ="數據庫原值：\r\n" +cmd.ExecuteScalar().ToString();
                           }
                       }

                   }


               }
               #endregion
               con.Close();
           }
       }


       public string GetAlterSql(string column)
       {
           StringBuilder sql = new StringBuilder();
           sql.Append("select  ");
           switch (column)
           {
               case "hymc": sql.Append("vc.vocation_code "); break;
               case "ztmc": sql.Append(" main.caption "); break;
               case "jgmc": sql.Append(" frame.frame_name "); break;
               case "jgmctyc": sql.Append(" frame.frame_name_synonyms "); break;
               case "ysjmc": sql.Append(" data.caption "); break;
               case "ysjmctyc": sql.Append(" data.synonyms "); break;
               case "sx": sql.Append(" data.attribute "); break;
               default: return "未知錯誤";

           }
           sql.Append("  from t_rvl_style_vocation  vc");
           sql.Append(" inner join t_rvl_style_main main on vc.vocation_code = main.vocation_code ");
           sql.Append("  inner join t_rvl_style_frame frame on main.id = frame.main_id ");
           sql.Append(" inner join t_rvl_style_metadata data on frame.id = data.frame_id where ");
           sql.Append(" vc.vocation_code=:hydm and  main.code =:ztdm and frame.frame_code=:jgdm ");
           sql.Append(" and  data.code=:ysjdm ");
           return sql.ToString();
       
       }
    }
}