LINQ查询独占返回重复项

Question

我正在研究这个LINQ查询。我希望结果列表根据EMailAddress1字段返回一个包含重复项的记录列表，并按EMailAddress1字段分组。

例如：

1. emailaddress1@gmail.com
2. emailaddress1@gmail.com
3. emailaddress2@gmail.com
4. emailaddress2@gmail.com
5. emailaddress2@gmail.com
6. emailaddress3@gmail.com
7. emailaddress3@gmail.com

等

对此有何建议？谢谢。

 var contacts = (from c in xrm.ContactSet 
                        where c.StateCode != 1 
                        orderby c.EMailAddress1, c.CreatedOn 
                        descending select new { 
                            c.FirstName, 
                            c.LastName, 
                            c.EMailAddress1, 
                            c.ContactId, 
                            c.CreatedOn }).ToList();

Answer 1

根据您之前的查询：

var duplicatedEmails = (from c in contacts
                        group c by c.EMailAddress1 into g
                        where g.Count() > 1
                        select g.Key).ToList();
var duplicatedContacts = contacts.Where(c => duplicatedEmails.Contains(c.EMailAddress1));