Creating orders in SAP system using .Net

You can handle it by creating an array and insert an object into Array.

Bapisdhd1 order_header_in = new Bapisdhd1();
order_header_in.DocType = "OR";
order_header_in.CollectNo = "111022";
order_header_in.SalesOrg = "11011";
order_header_in.DistrChan = "100";
order_header_in.Division = "000";
order_header_in.DlvBlock = "010";
order_header_in.PurchNoC = "TEST ORDER";
newOrder.OrderHeaderIn = order_header_in;