DataTable通过Select进行过滤

Posted 2022-11-07 tpf386

DataTable方法测试

  //测试DataTable的select
            DataTable dt = new DataTable();
            //a.OrderType,
            //a.[Status]
            dt.Columns.Add("No", typeof(String));
            dt.Columns.Add("Type", typeof(String));
            dt.Columns.Add("Status", typeof(String));

            dt.Rows.Add(new object[]  "A01", "N", "N1" );
            dt.Rows.Add(new object[]  "A01", "G", "G1" );
            dt.Rows.Add(new object[]  "A01", "T", "T1" );
            dt.Rows.Add(new object[]  "A01", "N", "N2" );
            dt.Rows.Add(new object[]  "A02", "G", "G1" );
            dt.Rows.Add(new object[]  "A02", "T", "T1" );
            dt.Rows.Add(new object[]  "A03", "N", "N1" );
            dt.Rows.Add(new object[]  "A04", "S", "S1" );
            dt.Rows.Add(new object[]  "A05", "G", "G1" );
            dt.Rows.Add(new object[]  "A05", "T", "T1" );

            DataRow[] arrRow = dt.Select("No=‘A01‘ and ((Type=‘N‘) or (Type=‘G‘ and Status<>‘G1‘) or(Type=‘T‘ and Status<>‘T1‘))");
            //Console.WriteLine(arrRow[0]["Type"]);
         
           var arrRow2= arrRow.Select<DataRow,DataRow>(dr=> 
                if (dr["Type"].ToString() == "N")
                    return dr;
                else
                   return null;
            );
            foreach(var r in arrRow2)
            
                if(r!=null)
                    Console.WriteLine(r["No"].ToString()+"===="+r["Status"].ToString());