Trying to Group By DataTable based upon multiple columns

[devashish1989 (Devashish Nigam)]

DTwithDuplicates.AsEnumerable().GroupBy(function(x) {x(“Product Name”).ToString, x(“Product ID”).ToString}).Select(function(g) g.CopyToDataTable)

Trying above expression and assigning to variable of <IEnumerable>

But its not working as intended and giving below output:

@Yoichi @loginerror @Pablito

[Yoichi]

Hi,

Can you try the following expression?

DTwithDuplicates.AsEnumerable.GroupBy(Function(r) Tuple.Create(r("Product Name").ToString, r("Product ID").ToString)).Select(Function(g) g.CopyToDataTable).ToList

Regards,

[ppr (Peter Preuss)]

Also have a look here:

[HowTo] Overview on different options for grouping data and processing the groups

This HowTo introduces on the different options for grouping data from a datatable in order to process the grouped data. Introduction Grouping data and processing the grouped data is a common scenario e.g. when the grouped data is to aggregate like summing up, find maximum, get the average or concatening items. Lets have a look on following data: [grafik] A possible scenario could be: Create a report containing following information: the region code the sum of CaseCount per RegionCode t…

[devashish1989 (Devashish Nigam)]

@Yoichi : great Thanks a lot it works

Is there a Linq way to created derived column let say amount = Price*QTY from existing 2 columns Price and QTY without iterating for loop.
Thanks in advance

[ppr (Peter Preuss)]

in that case we often can use the expression property of a datacolumn

DataColumn.Expression Property (System.Data)

[devashish1989 (Devashish Nigam)]

Let me try this