比较两个Dataset中指定列是否有相同的数据

Question

有两个Dataset，分别都只有一张表，每张表指定一列，如何判断指定的两列有相同的数据

Answer 1

{
                #region 测试数据
                DataSet ds1 = new DataSet();
                DataTable dt1 = new DataTable();
                dt1.Columns.Add(new DataColumn("id1", typeof(string)));
                dt1.Columns.Add(new DataColumn("name1", typeof(string)));
                dt1.Rows.Add("1", "a");
                dt1.Rows.Add("2", "b");
                dt1.Rows.Add("3", "c");
                ds1.Tables.Add(dt1);                DataSet ds2 = new DataSet();
                DataTable dt2 = new DataTable();
                dt2.Columns.Add(new DataColumn("id2", typeof(string)));
                dt2.Columns.Add(new DataColumn("name2", typeof(string)));
                dt2.Rows.Add("4", "a");
                dt2.Rows.Add("5", "b");
                dt2.Rows.Add("1", "c");
                ds2.Tables.Add(dt2);
                #endregion                 Console.WriteLine(ExistsSameDataByDataColumn(ds1.Tables[0], "id1", ds2.Tables[0], "id2"));
            }            static bool ExistsSameDataByDataColumn(DataTable dt1, string col1, DataTable dt2, string col2)
            {
                foreach (DataRow row in dt1.Rows)
                {
                    if (dt2.Select(string.Format("{0}='{1}'", col2, row[col1].ToString())).Length > 0) return true;
                }
                return false;
               
            }