如何使用linq语句查询？

Question

我有两个对象

List<Report> 
List<Newsletter>

我需要某些属性，比如

Id
Date
Status
text

来自两个名单。有没有办法合并这些列表并使用linq语句查询它以将特定属性作为单独的列表返回？ 请帮忙。

对象的结构如下：

Report
{
    int id,
    datetime reportDate, 
    enum Status,
    string text
};

Newsletter
{
    int id, 
    datetime newsletterDate,
    string Status,
    string text
};

Answer 1

var items = 
      reportList.Select(x =>  new { x.Id, x.Date, x.Status, x.text })
      .Concat(
        newsList.Select(x =>  new { x.Id, x.Date, x.Status, x.text }) );

---

更新，以平衡状态属性：

var items = 
      reportList.Select(x =>  new { x.Id, x.Date, Status = x.Status.ToString(), x.text })
      .Concat(
        newsList.Select(x =>  new { x.Id, x.Date, Status, x.text }) );

Answer 2

假设列表中包含公共列并在它们之间应用连接..

您可以加入，然后获取以下数据

var data = form a in lista
join b in listb on
a.id equals b.id
select new {id=a.id, Date= b.Date, Status=a.Sttus, text=b.Text};

以下是两个表用户和userclient之间的连接图像

查看完整文章：Case 4 - JOINING TWO TABLE

Answer 3

var reps = reposts.Select(r => new { Id = r.Id, Date = r.Date, Status = r.Status, Text = r.Text});
var news = newsletters.Select(n => new { Id = r.Id, Date = r.Date, Status = r.Status, Text = r.Text});
var result = reps.Union(news);

Answer 4

 var query = reports.Select(x => new { x.Id, x.Date, Status = Enum.GetName(typeof(Status), x.Status), x.Text })
.Union(news.Select(x => new { x.Id, x.Date, x.Status, x.Text }));