匿名类型的字符串聚合

Question

I want to concat multiple string value into single string with comma separated,i tried using aggregate function but it shows cannot convert string to how to fix this issue,

I tried below code

var res = (from e in WYNKContext.SurgeryAssigned.Where(x => x.CmpID == cmpid && x.IsCancelled == false)
                       select new
                       {
                           ID = e.SAID,
                           UIN = e.UIN,
                           SurgeryDate = e.SurgeryDate,
                           SurgeryID = e.SurgeryID,
                           Surgery = ((from st in WYNKContext.SurgeryTran.                         
                                       Where(x => x.SurgeryID ==  e.SurgeryID)
                                       select new
                                       {
                                             desc = icdmaster
                                                  .Where(x => x.ID == 
                                                   st.IcdSpecialityCode).Select(x => 
                                                   x.SpecialityDescription).FirstOrDefault(),
                                       }).ToList()).Aggregate((a, b) => a.desc + "," + b.desc),

                                     }).ToList();

I want Output like inside surgery property like = string1,string 2,etc....

without using aggregate i am getting as count in Surgery Property

 var res = (from e in WYNKContext.SurgeryAssigned.Where(x => x.CmpID == cmpid && x.IsCancelled == false)
                           select new
                           {
                               ID = e.SAID,
                               UIN = e.UIN,
                               SurgeryDate = e.SurgeryDate,
                               SurgeryID = e.SurgeryID,
                               Surgery = (from st in WYNKContext.SurgeryTran.Where(x => x.SurgeryID == e.SurgeryID)
                                      select new
                                      {
                                          icd = icdmaster.Where(x => x.ID == st.IcdSpecialityCode).Select(x => x.SpecialityDescription).FirstOrDefault(),
                                       }).ToList(),

                                         }).ToList();

also tried string join:

   Surgery = string.Join(",", (from st in WYNKContext.SurgeryTran.Where(x => x.SurgeryID == e.SurgeryID)
                              select new
                              {
                                  icd = icdmaster.Where(x => x.ID == st.IcdSpecialityCode).Select(x => x.SpecialityDescription).FirstOrDefault(),
                              }).ToList()),

but in output i am getting like this

Surgery ={ icd = CORNEA },{ icd = CATARACT/IOL }

can some one tell what i did wrong in string.join.....

Answer 1

The string class has a static method named Join , which takes in a collection of items and a string to join them with, which should work for you here.

If I'm reading your code correctly, it would look something like this:

Surgery = string.Join(",", WYNKContext.SurgeryTran
    .Where(surgTran => surgTran.SurgeryID == e.SurgeryID)
    .Select(surgTran => icdmaster
        .Where(icd => icd.ID == surgTran.IcdSpecialityCode)
        .Select(icd => icd.SpecialityDescription)
        .FirstOrDefault())),