如何使用EF连接两个数据传输对象(DTO)?[已编辑]

我愿意接受任何改进或建议,我解决了它如下:

用文字表示 DTOs

在代码中

    public class PatRegDto

    {
        public string Action { get; set; }
        private Int64 _FileId;
        public Int64 FileId
        {
            get
            {
                return this._FileId;
            }
            set
            {
                this._FileId = value;
            }
        }
        public string FName { get; set; }
        public string MName { get; set; }
        public string LName { get; set; }
        public string fullname
        {
            get { return FName + " " + MName + " " + LName; }
        }
        public DateTime Dob { get; set; }
        public List<PatParDto> PartnerInfo { get; set; }
    }
    public class PatParDto

    {
        public string Action { get; set; }
        public long RecId { get; set; }
        public long FileId { get; set; }
        public long ParFileId { get; set; }
        public DateTime SDate { get; set; }
        public DateTime? EDate { get; set; }
        public DateTime dob { get; set; }
        public string FullName { get; set; }
    }

控制器是

    [HttpGet("{id}")]
    public async Task<IActionResult> GetPatReg([FromRoute] long id)
    {

        if (!ModelState.IsValid)
        {
            return BadRequest(ModelState);
        }

        // 1 select Parent Record
        var PatientInfo = await _context.PatReg 
            .Where(a => a.FileId == id)
            .Select(b => new PatRegDto
            {
                Action = "Get",
                FileId = b.FileId,
                FName = b.FName,
                MName = b.MName,
                LName = b.LName,
                Dob = b.Dob,
            }).ToListAsync();
        // 2 select Child Record
        var PartnerInfo = await _context.PatPar
        .Where(s=>s.FileId==id)
        .Select(m => new PatParDto 
        {
            RecId = m.RecId,
            FileId = m.FileId,
            ParFileId = m.ParFileId,
            SDate = m.SDate,
            EDate = m.EDate,
        }).ToListAsync();

        // 3 Fetch more data (not in the original model)
        for (int i = 0; i < PartnerInfo.Count; i++)

        {

            PartnerInfo[i].FullName = _context.PatReg.Where(a => a.FileId == PartnerInfo[i].ParFileId)
                                   .Select(t => new { t.fullname })
                                   .Single().fullname;
            PartnerInfo[i].dob = _context.PatReg.Where(a => a.FileId == PartnerInfo[i].ParFileId)
                                   .Select(t => new { t.Dob })
                                   .Single().Dob;

            PartnerInfo[i].Action = "Get";

        }

         // 4 Join parent and child data 
        for (int i = 0; i < PatientInfo.Count; i++)

        {

            PatientInfo[i].PartnerInfo = PartnerInfo.Where(a => a.FileId == PartnerInfo[i].FileId).ToList();

        }



        if (PatientInfo == null)
        {
            return NotFound();
        }

        var DataRes = new {
            sdata = PatientInfo
        };

        return Ok(DataRes);
    }

{
    "sdata": [{
        "action": "Get",
        "fileId": 1708010001,
        "fName": "*****",
        "mName": "*****",
        "lName": "*****",
        "fullname": "*******",
        "dob": "1984-04-26T00:00:00",
        "dateCreated": "2017-09-06T10:50:16.766162Z",
        "partnerInfo": [{
            "action": "Get",
            "recId": 2,
            "fileId": 1708010001,
            "parFileId": 1708010002,
            "sDate": "1999-12-12T00:00:00",
            "eDate": null,
            "dob": "1984-04-26T00:00:00",
            "fullName": "********"
        }, {
            "action": "Get",
            "recId": 3,
            "fileId": 1708010001,
            "parFileId": 1708010003,
            "sDate": "1955-12-14T00:00:00",
            "eDate": null,
            "dob": "1984-04-26T00:00:00",
            "fullName": "********"
        }]
    }]
}