How to write database value in text file on defined format

I read a delimited text file into dataset. i am writing these dataset values line by line in another text file. my C# syntax is :

try
            {
                DataClasses1DataContext db = new DataClasses1DataContext();

                var r = from p in db.Products
                        select p;
                //DataTable TarGetTable;
                //TarGetTable = AddDataToTable();
                String TargetStringFilePath;
                TargetStringFilePath = @"c:\aaa.txt";
                StreamWriter fw = File.CreateText(TargetStringFilePath);

                foreach (Product drPrintRow in r)
                {

                    //drPrintRow[drPrintRow]
                    String str = drPrintRow.CategoryID.ToString();
                    str +=" "+ drPrintRow.Discontinued.ToString();
                    str +=" "+ drPrintRow.ProductID.ToString();
                    str += " "+drPrintRow.ProductName.sToString();
                    fw.WriteLine(str);
                }


                fw.Flush();

                fw.Close();
                //}
            }
            catch (Exception ex)
            {
            }

I want this output in bellow format

                                        CUSTOMERWISE ORDER STATUS REPORT
                                        ================================
 Trading Date : 1-2-2010                                                                           Date :1-2-2010
                                                                                                     Time :15:00:52                    
      HOWLA TYPE               FILL TYPE              MKT TYPE                   ORDER STATUS                     
    --------------     -------------------------     -----------     ---------------------------------------------
    D : DVP            MF   : MinimumFill            P : PUBLIC      AC : ACTIVE       CF : CompletelyFilled      
    N : NORMAL         PF   : Partial Fill           S : SPOT        NA : NOTACTIVE    FR : FilledAndRejected     
    U : UNSPECIFIED    FOK  : FillOrKill             O : ODDLOT      XE : Executed     EX : Expired               
                       AON  : AllOrNone              B : BLOCK       RJ : Rejected     OM : OriginalOrderModified 
                       PFAK : PartialFillAndKill                     DE : Deactivated  PF : PartiallyFilled       
                                                                     DL : Deleted      CR : CrossingReported      
_______________________________________________________________________________________________________________________
CUSTOMER  |INSTRUMENT| BROKER  | Quantity|B |   PRICE  | BALANCE |HOWLA| EXPIRY   | MKT|FILL|ORDER |  TORN   |  TORN   |
          |          | ORDER   |         |/ |    Tk.   |   QTY   |TYPE | DATE     |TYPE|TYPE|STATUS| PREFIX  | SUFFIX  |
          |          | REFNO   |         |S |          |         |     |          |    |    |      |   NO    |   NO    |
__________|__________|_________|_________|__|__________|_________|_____|__________|____|____|______|_________|_________|
00002     |BSRMSTEEL |109379297|      500|S |   1325.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 41500123|
          |CITYBANK  |109379298|      200|S |    940.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  6300609|
          |POWERGRID |109379303|      500|S |    789.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  6000269|
          |SPCERAMICS|109379306|     5000|S |     93.60|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 40200627|
          |CITYBANK  |109379439|     2000|S |    912.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  6300918|
00004     |PREMIERBAN|109379645|      550|B |    402.75|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 32601990|
          |PLFSL     |109379725|      100|B |    660.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 27800430|
          |MAKSONSPIN|109379373|     2000|S |    110.70|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 41400304|
          |MPETROLEUM|109379654|      100|S |    329.00|      100|  N  |01-02-2010| P  | PF |  AC  |201003201| 36001036|
          |BXPHARMA  |109379867|      200|S |    185.50|      200|  N  |01-02-2010| P  | PF |  AC  |201003201|  9302082|
00011     |PADMAOIL  |109379692|     1000|S |    811.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 15500272|
          |MPETROLEUM|109379989|     1000|S |    324.70|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 36001454|
          |CONFIDCEM |109380341|      500|S |   1614.75|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  6500878|
          |          |109380346|      500|S |   1616.00|      240|  N  |01-02-2010| P  | PF |  PF  |201003201|  6500891|
          |          |109380351|      500|S |   1615.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  6500905|
00012     |APEXTANRY |109379064|      100|B |   1373.50|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  1300042|
          |          |109379154|      100|B |   1365.00|      100|  N  |01-02-2010| P  | PF |  AC  |201003201|  1300127|
          |          |109379328|      100|B |   1385.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  1300301|
          |UNIONCAP  |109379471|      500|B |    143.00|        0|  N  开发者_开发百科|01-02-2010| P  | PF |  CF  |201003201|  8000591|
          |          |109379535|      500|B |    143.50|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  8000651|
          |          |109379774|     1000|B |    142.30|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  8000931|
          |          |109380425|      500|B |    142.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  8001532|
          |PREMIERBAN|109379218|      100|S |    399.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 32600814|
          |SUMITPOWER|109380383|      100|S |   1324.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 28401076|
          |          |109380438|       50|S |   1321.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201| 28401129|
00013     |APEXTANRY |109379034|      100|B |   1375.00|        0|  N  |01-02-2010| P  | PF |  CF  |201003201|  1300016|

How to write dataset value in text file in specified format.Is there any existing software that can do that for me.

I use Northwind database on C# syntax.HOw to write this product table information in above format.

I'd suggest starting with the string.Format method and check the additional references on the documentation page for help in determining the proper custom format strings.

I think you are looking for string.Format(...). This allows you to format many different data types into a defined string format.