c# - LINQ Syntax for Selecting a Parameter to Be Copied -


i have code sort collection in linq in c#. want group housename sum on volumes, order collection, pass third parameter, pctvol, new sorted collection. doing wrong? know problem lies in pctvol = group.selecct(item => item.pctvol) line.

            var inbetween = this.groupby(item => item.housename)              .select(group =>                     new dataitem                     {                         housename = group.key,                         volume = group.sum(item => item.volume),                         pctvol = group.select(item => item.pctvol)                     })              .tolist();             observablecollection<dataitem> objsort = new observablecollection<dataitem>(inbetween.orderby(dataitem =>                                     dataitem.volume));             return objsort;

what kind of value want pctvol have? code, looks dataitem.pctvol ienumerable containing pctvol values in group.

if want single value, , pctvol values in each group guaranteed same, take value first element, this: pctvol = group.first().pctvol


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