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Question

尝试获得一个IEnumerable WorkOrderHeader给定以下表结构:

OrderHeader 1:many OrderDetails
OrderDetail 1:1 WorkOrderHeader

代码:

public IEnumerable<WorkOrderHeader> GetInProcessWorkOrdersForOrderBy(OrderHeader orderHeader)
{
    var orderDetails = orderHeader.OrderDetails;
    var workOrders= orderDetails.Select(od => od.WorkOrderHeaders.Where(woh => woh.StatusId < (int)WorkOrderStatus.Complete));
    return workOrders;
}

返回一个嵌套的IEnumerable<IEnumerable<WorkOrderHeader>>。如何获得内部的IEnumerable<WorkOrderHeader> ?

Answer 1

我想你是在寻找SelectMany

var workOrders= orderDetails.SelectMany(od => ...)