Creating a DataTable in X++ - datatable

Question

I'm trying to create a datatable in microsoft ax x++.
I need to return some information back to a webservice. Problem is i'm having trouble getting this code to work. it runs to the point where i try to add a column because apparently that function doesn't work....
Does anyone have the code in full to create a datatable in x++. this code works up until the column code.. because basically what i'm doing is query some information and returning it back to a webservice.. unless theres another way to return multiple information back to a webservice that uses c#
System.Data.DataTable dt = new System.Data.DataTable("MyTable");
System.Data.DataColumnCollection columns = dt.get_Columns();
System.Data.DataColumn ProductName;
System.Data.DataColumn QtyOrdered;
System.Data.DataColumn ProductID;
System.Data.DataRow row;
ProductID = new System.Data.DataColumn("ProductID", System.Type::GetType("System.Int32"));
ProductName = new System.Data.DataColumn("ProductName", System.Type::GetType("System.String"));
QtyOrdered = new System.Data.DataColumn("QtyOrdered", System.Type::GetType("System.String"));
// dt.Columns.Add(ProductID);
// dt.Columns.Add(ProductName);
// dt.Columns.Add(QtyOrdered);
row=dt.NewRow();

Answer 1

Did you try replacing lines
// dt.Columns.Add(ProductID);
// dt.Columns.Add(ProductName);
// dt.Columns.Add(QtyOrdered);
with
columns.Add(ProductID);
columns.Add(ProductName);
columns.Add(QtyOrdered);
?
P.S. To populate the row:
System.Data.DataRowCollection rows = dt.get_Rows();
...
row = dt.NewRow();
row.set_Item("ProductID", 1);
row.set_Item("ProductName", "PN");
row.set_Item("QtyOrdered", "QO");
rows.Add(row);
I suggest you to read some MSDN articles such as .NET Interop from X++, How To Use X++ Syntax for CLR Arrays, etc. - it should help you understand how to use .NET assemblies from X++.