小编Ecl*_*pse的帖子

是否可以使用SelectMany()并使其行为像左连接？

我试图将实体对象展平为表格格式,以便我可以将其用作.rdlc报告的数据源.只要有一个子对象,SelectMany()的工作方式就像一个魅力,但我希望看到所有的父对象,无论它是否有子节点.

public class Owner
{
    public int ownerID { get; set; }
    public string ownerName { get; set; }
    public List<Pet> pets { get; set; }
}

public class Pet
{
    public int petID { get; set; }
    public string petName { get; set; }
    public string petType { get; set; }
}

    public void GetOwners()
    {
        List<Owner> owners = new List<Owner>();
        owners.Add(new Owner{ownerID=1, ownerName="Bobby", pets = null});
        owners.Add(new Owner
        {
            ownerID = 2,
            ownerName = "Ricky",
            pets = …