Question

I’d like to convert a list of EF objects to a dictionary. I somewhat accomplished this, with one drawback: I can’t figure out how to add multiple of the objects to one key,value pair based on an attribute of that object.

For example say I have an Entity Framework object TblValue with three values – ValueID, ValueNm, CodeID.

The CodeID will be shared among the objects – some may be the same and some may be different.

I would like to create a Dictionary<TblCode, List<TblData>>. (TblCode comes from CodeID.) Basically, I want to create a dictionary of this list of items where each list is separated & grouped by the CodeID, using LINQ.

The LINQ statement I was using before was working, but it wouldn’t do any grouping. Is this pretty close, or is LINQ not appropriate for this? Would a foreach loop be better?

var splitTimes = times.Cast<TblValue>().ToDictionary(o => tr.GetCode(o.CodeID));

clarification – I am unable to group the values….I cannot create a Dictionary<TblCode, List<TblValue>>, I can only create a Dictionary<TblCode, TblValue>

Answer 1

I found a way to do it, the_joric’s answer was close but I had to explicitly call ToList() on the values.

var splitTimes = times.GroupBy(x => x.ProjCdId).ToDictionary(o => tr.GetProjCd(o.Key), o => o.ToList());