如何从多个表LINQ中选择

Question

这是我的查询

var query = from t1 in context.HrEmployee
                            join t2 in context.ResPartner on t1.PartnerId equals t2.Id
                            join t3 in context.HrDepartment on t1.DepartmentId equals t3.Id into ed
                            from t3 in ed.DefaultIfEmpty()
                            select new
                            {
                                t1,
                                EmployeeCode = t2.PartnerCode,
                                EmployeeName = t2.PartnerName,
                            };

输出

----------

我可以输出这样的数据吗？

[ 
   { 
      "id":"37f1b447-d242-4509-baa1-04f1647bdafe",
      "createUid":"ff9ca515-a7aa-4ae4-884d-505cdaf017fe",
      "createDate":"2019-12-25T23:12:28.481578",
      "writeUid":"ff9ca515-a7aa-4ae4-884d-505cdaf017fe",
      "writeDate":"2019-12-26T00:00:23.73043",
      "companyId":"6efb7fda-dbe4-4bdf-a7a9-8f2876daf59a",
      "EmployeeCode":"TEST",
      "EmployeeName":"TEST"
   }
]

我可以编写一个linq查询以输出我上面想要的json数据，请帮助我吗？

---

Answer 1

var query = from t1 in context.HrEmployee
            join t2 in context.ResPartner on t1.PartnerId equals t2.Id
            join t3 in context.HrDepartment on t1.DepartmentId equals t3.Id into ed
            from t3 in ed.DefaultIfEmpty()
            select new
            {
              id = t1.id,
              createUid = t1.createUid,
              createDate = t1.createDate,
              writeUid = t1.writeUid,
              writeDate = t1.writeDate,
              companyId = t1.companyId,
              EmployeeCode = t2.PartnerCode,
              EmployeeName = t2.PartnerName,
            };

并序列化您的查询。将给出预期的结果