LINQ查询(Group BY)？

Question

考虑以下对象:

public class Address { public string city; public string state; public string country; }

如果我有一个地址列表,我将如何使用LINQ获取城市,州和国家匹配的计数列表.

所以我的结果看起来像这样:

• "princeton""nj""usa"122
• "奥斯汀""tx""美国"44
• "la""ca""usa"1
• "princton""na""uk"3
• ....

谢谢!

Answer 1

比Marc的答案更进了一步(他在我发布之前编辑过!).大声笑

var qry = from addr in addresses
          group addr by new { addr.city, addr.state, addr.country } into grp
          select new
          {
            city = grp.Key.city,
            state = grp.Key.state,
            country = grp.Key.country,
            count = grp.Count(),
          };