两个 DataTable 读取重复数据，dataTable1与dataTable2不同

protected void Page_Load(object sender, EventArgs e)
       {
           DataTable dt = new DataTable();
           dt.Columns.Add("col");
           for (int i = 5; i >0;i=i-2)
           {
               DataRow row = dt.NewRow();
               row["col"] = "车" + i;
               dt.Rows.Add(row);
           }


           DataTable dt1 = new DataTable();
           dt1.Columns.Add("col1");
           for (int i = 1; i <= 4; i++)
           {
               DataRow row = dt1.NewRow();
               row["col1"] = "车" + i;
               dt1.Rows.Add(row);
           }

           DataTable resultTable = cf(dt,dt1);
           Response.Write("重复：");
           for (int i = 0; i < resultTable.Rows.Count; i++)
               Response.Write(resultTable.Rows[i]["col"].ToString());

           Response.Write("<br/>");


           resultTable = bcfbyd1tod2(dt, dt1);
           Response.Write("不重复 d1tod2：");
           for (int i = 0; i < resultTable.Rows.Count; i++)
               Response.Write(resultTable.Rows[i]["col"].ToString());

           Response.Write("<br/>");


           resultTable = bcfbyd2tod1(dt, dt1);
           Response.Write("不重复 d2tod1：");
           for (int i = 0; i < resultTable.Rows.Count; i++)
               Response.Write(resultTable.Rows[i]["col"].ToString());

           Response.Write("<br/>");

       }

       /// <summary>
       /// 取重复
       /// </summary>
       /// <param name="dt"></param>
       /// <param name="dt1"></param>
       /// <returns></returns>
       private DataTable cf(DataTable dt, DataTable dt1)
       {
           DataTable myTable = dt.Clone();

           for (int i = 0; i < dt.Rows.Count; i++)
           {
               DataRow[] sRow= dt1.Select("col1='"+dt.Rows[i]["col"].ToString()+"'");

               if (sRow.Length > 0)
               {
                  DataRow row= myTable.NewRow();
                  row["col"] = dt.Rows[i]["col"].ToString();
                  myTable.Rows.Add(row);
               }
           }

           return myTable;
       }


       /// <summary>
       /// 不重复d1tod2
       /// </summary>
       /// <param name="dt"></param>
       /// <param name="dt1"></param>
       /// <returns></returns>
       private DataTable bcfbyd1tod2(DataTable dt, DataTable dt1)
       {
           DataTable myTable = dt.Clone();

           for (int i = 0; i < dt.Rows.Count; i++)
           {
               DataRow[] sRow = dt1.Select("col1='" + dt.Rows[i]["col"].ToString() + "'");

               if (sRow.Length == 0)
               {
                   DataRow row = myTable.NewRow();
                   row["col"] = dt.Rows[i]["col"].ToString();
                   myTable.Rows.Add(row);
               }
           }

           return myTable;
       }


       /// <summary>
       /// 不重复d1tod2
       /// </summary>
       /// <param name="dt"></param>
       /// <param name="dt1"></param>
       /// <returns></returns>
       private DataTable bcfbyd2tod1(DataTable dt, DataTable dt1)
       {
           DataTable myTable = dt.Clone();

           for (int i = 0; i < dt1.Rows.Count; i++)
           {
               DataRow[] sRow = dt.Select("col='" + dt1.Rows[i]["col1"].ToString() + "'");

               if (sRow.Length == 0)
               {
                   DataRow row = myTable.NewRow();
                   row["col"] = dt1.Rows[i]["col1"].ToString();
                   myTable.Rows.Add(row);
               }
           }

           return myTable;
       }
http://blog.csdn.net/yeness/article/details/7817032