如何使用 linq 或 lambda 表达式连接两个列表

我有两个名单 List<WorkOrder>List<PlannedWork>我想加入这两个名单上的工作单号码详细如下。换句话说,我有一个计划工作的列表,但是我需要知道 workOrderNumber 的工作描述。

我对 linq 和 lambda 表达式都是新手,我还没有完全理解它们。

class WorkOrder
{
public int WorkOrderNumber { get; set; }
public string WorkDescription { get; set; }
}


class PlannedWork
{
public int WorkOrderNumber { get; set; }
public DateTime ScheduledDate { get; set; }
}
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听起来好像你想要这样的东西:

var query = from order in workOrders
join plan in plans
on order.WorkOrderNumber equals plan.WorkOrderNumber
select new
{
order.WorkOrderNumber,
order.Description,
plan.ScheduledDate
};

使用扩展方法(而不是 linq 查询语法)完成此操作的方法如下:

var results = workOrders.Join(plans,
wo => wo.WorkOrderNumber,
p => p.WorkOrderNumber,
(order,plan) => new {order.WorkOrderNumber, order.WorkDescription, plan.ScheduledDate}
);
 public class State
{
public int SID { get; set; }
public string SName { get; set; }
public string SCode { get; set; }
public string SAbbrevation { get; set; }
}


public class Country
{
public int CID { get; set; }
public string CName { get; set; }
public string CAbbrevation { get; set; }
}




List<State> states = new List<State>()
{
new  State{  SID=1,SName="Telangana",SCode="+91",SAbbrevation="TG"},
new  State{  SID=2,SName="Texas",SCode="512",SAbbrevation="TS"},
};


List<Country> coutries = new List<Country>()
{
new Country{CID=1,CName="India",CAbbrevation="IND"},
new Country{CID=2,CName="US of America",CAbbrevation="USA"},
};


var res = coutries.Join(states, a => a.CID, b => b.SID, (a, b) => new {a.CName,b.SName}).ToList();