需要對DataTable分組求和的語法：VB.net 和C#中還有點不太一樣。最後試了好多方法，要這麼寫

我的dataTabel資料：

  (From p In dataTabel.AsEnumerable()

  Group By x= New With { Key.a =p.Item("name")} Into Grp = Group Select dataTabel.Clone.LoadDataRow (New Object()

   {grp()(),grp.Sum(Function ( r )

  if(String.IsNullOrEmpty(r("fen").ToString)
 

  or String.IsNullOrWhiteSpace(r("fen").ToString),,Convert.ToDouble(r("fen").ToString)))},False)).CopyToDataTable

最後成功列印：