这段代码：
@H_301_2@var customers = from cust in Customers
group cust by new {cust.Country} into grouping
select new
{
Country = grouping.Key.Country,Customers = grouping
};
customers.ToList().ForEach(g =>
Console.WriteLine("{0} has {1} customers: {2}",g.Country,g.Customers.Count(),String.Join(",",g.Customers.Select(x => "#. " + x.CompanyName).ToArray())
));
customers.Dump();
产生这些结果：
@H_301_2@Argentina has 3 customers: #. Cactus Comidas para llevar,#. Océano Atlántico Ltda.,#. Rancho grande Austria has 2 customers: #. Ernst Handel,#. Piccolo und mehr Belgium has 2 customers: #. Maison Dewey,#. Suprêmes délices Brazil has 9 customers: #. Comércio Mineiro,#. Familia Arquibaldo,#. Gourmet Lanchonetes,#. Hanari Carnes,#. Que Delícia,#. Queen Cozinha,#. Ricardo Adocicados,#. Tradição Hipermercados,#. Wellington Importadora Canada has 3 customers: #. Bottom-Dollar Markets,#. Laughing Bacchus Wine Cellars,#. Mère Paillarde Denmark has 2 customers: #. Simons bistro,#. Vaffeljernet ...如何用索引/计数替换“#”,以便得到如下结果：
@H_301_2@Argentina has 3 customers: 1. Cactus Comidas para llevar,2. Océano Atlántico Ltda.,3. Rancho grande ...解决方法
@H_301_2@customers.ToList().ForEach(g => Console.WriteLine("{0} has {1} customers: {2}",string.Join(",g.Customers.Select((x,i) => i + ". " + x.CompanyName).ToArray())));
