asp.net - Something not quiet right with my linq statement binding to a listview -

i trying bind grouped linq statement asp.net listview. problem when result been returned list view result this.

system.linq.enumerable+whereenumerableiterator1[transactiondetail] 20.5 system.linq.enumerable+whereenumerableiterator1[transactiondetail] 7.3

my code nothing special

    list<transactiondetail> transactions = new list<transactiondetail>();         transactions.add(new transactiondetail { purchasedate = datetime.now, transactionamount = 2, transactionid = 1, ispurchase = true });         transactions.add(new transactiondetail { purchasedate = datetime.now, transactionamount = 2.2, transactionid = 2, ispurchase = true });         transactions.add(new transactiondetail { purchasedate = datetime.now, transactionamount = 2.9, transactionid = 3, ispurchase = false });         transactions.add(new transactiondetail { purchasedate = datetime.now, transactionamount = 4, transactionid = 4, ispurchase = true });         transactions.add(new transactiondetail { purchasedate = datetime.now, transactionamount = 2.2, transactionid = 5, ispurchase = false });         transactions.add(new transactiondetail { purchasedate = datetime.now, transactionamount = 5, transactionid = 6, ispurchase = true });         transactions.add(new transactiondetail { purchasedate = datetime.now, transactionamount = 5, transactionid = 7, ispurchase = true });         transactions.add(new transactiondetail { purchasedate = datetime.now, transactionamount = 2.3, transactionid = 8, ispurchase = true });         transactions.add(new transactiondetail { purchasedate = datetime.now, transactionamount = 2.2, transactionid = 9, ispurchase = false });               var grouped = t in transactions                       group t t.ispurchase g                       select new {                         addedpurchase = g.where(s=>s.ispurchase),                        balance = g.sum(s=>s.transactionamount)                       };           lsttransactions.datasource = grouped;         lsttransactions.databind(); 

my listview looks somthing this

 <itemtemplate>     <span> <%# eval("addedpurchase")%></span><span> <%# eval("balance")%></span>     </itemtemplate> 

why seeing system.linq.enumerable+whereenumerableiterator1[webui.transactiondetail] 20.5 returned result. interested in addedpurchase , balance

i cant offer explanation why happening might try following 2 fixes:

1. add ".tolist()" end of linq query. should stop seeing "whereenumerableiterator1" type description popping up.

2. add further linq query can select new list of listitems grouping:

   lsttransactions.items.addrange( grouped.select(x => new listitem(x.addedpurchase, x.balance) )

edit:

the problem in fact lies second linq query, select out new anonymous type variable grouped:

addedpurchase = g.where(s=>s.ispurchase) 

added purchase have value of where() iterator. im not sure purpose of "addedpurchase" variable if example wanted signify purchse had been made, do:

addedpurchase = g.where(s=>s.ispurchase).count() > 0