Linq select to new object

Question

I have a linq query   var x    from t in types select t  GroupBy g   gt g Type    which groups objects by their type  as a result I want to have single new object containing all of the grouped objects and their count  Something like this   type1  30     type2  43     type3  72   to be more clear  grouping results should be in one object not an object per item type

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var x   from t in types         group t by t Type into grouped         select new   type   grouped Key                       count   grouped Count

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All of the grouped objects  or all of the types  It sounds like you may just want   var query   types GroupBy t   gt  t Type                    Select g   gt  new   Type   g Key  Count   g Count        foreach  var result in query        Console WriteLine   0    1    result Type  result Count       EDIT  If you want it in a dictionary  you can just use   var query   types GroupBy t   gt  t Type                    ToDictionary g   gt  g Key  g   gt  g Count       There s no need to select into pairs and then build the dictionary

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The answers here got me close  but in 2016  I was able to write the following LINQ   List lt ObjectType gt  objectList   similarTypeList Select o   gt      new ObjectType               PropertyOne   o PropertyOne          PropertyTwo   o PropertyTwo          PropertyThree   o PropertyThree        ToList

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This is a great article for syntax needed to create new objects from a LINQ query   But  if the assignments to fill in the fields of the object are anything more than simple assignments  for example  parsing strings to integers  and one of them fails  it is not possible to debug this  You can not create a breakpoint on any of the individual assignments   And if you move all the assignments to a subroutine  and return a new object from there  and attempt to set a breakpoint in that routine  you can set a breakpoint in that routine  but the breakpoint will never be triggered   So instead of   var query2   from c in doc Descendants  SuggestionItem                   select new SuggestionItem                          Phrase   c Element  Phrase   Value                          Blocked   bool Parse c Element  Blocked   Value                            SeenCount   int Parse c Element  SeenCount   Value                              Or  var query2   from c in doc Descendants  SuggestionItem                            select new SuggestionItem c     I instead did this   List lt SuggestionItem gt  retList   new List lt SuggestionItem gt      var query   from c in doc Descendants  SuggestionItem   select c   foreach  XElement item in query        SuggestionItem anItem   new SuggestionItem item       retList Add anItem       This allowed me to easily debug and figure out which assignment was failing  In this case  the XElement was missing a field I was parsing for to set in the SuggestionItem   I ran into these gotchas with Visual Studio 2017 while writing unit tests for a new library routine

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If you want to be able to perform a lookup on each type to get its frequency then you will need to transform the enumeration into a dictionary   var types   new    typeof string   typeof string   typeof int    var x   types          GroupBy type   gt  type           ToDictionary g   gt  g Key  g   gt  g Count     foreach  var kvp in x        Console WriteLine  Type  0   Count  1    kvp Key  kvp Value     Console WriteLine  string has a count of  0    x typeof string

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Read   101 LINQ Samples in that LINQ - Grouping Operators from Microsoft MSDN site   var x   from t in types  group t by t Type          into grp              select new   type   grp key  count   grp Count        forsingle object make use of stringbuilder and append it that will do or convert this in form of dictionary          fordictionary    var x    from t in types  group t by t Type      into grp          select new   type   grp key  count   grp Count          ToDictionary  t   gt  t type  t   gt  t count          for stringbuilder not sure for this    var x   from t in types  group t by t Type          into grp              select new   type   grp key  count   grp Count        StringBuilder MyStringBuilder   new StringBuilder       foreach  var res in x                 is separator between to object        MyStringBuilder Append result Type         result Count                 Console WriteLine MyStringBuilder ToString

[c#] Linq select to new object

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