c# - Group by for list in list -

i have list of issues : list<issue> issue class :

public class issue : baseentity {     private string m_keystring;      [jsonproperty("expand")]     public string expand { get; set; }      [jsonproperty("id")]     public int id { get; set; }      #region special key solution     [jsonproperty("key")]     public string proxykey     {                 {             return key.tostring();         }         set         {             m_keystring = value;         }     }      [jsonignore]     public issuekey key     {                 {             return issuekey.parse(m_keystring);         }     }     #endregion special key solution      [jsonproperty("fields")]     public fields fields { get; set; } } 

class fields looks :

public class fields {     [jsonproperty("summary")]     public string summary { get; set; }      [jsonproperty("assignee")]     public assignee assignee { get; set; }      [jsonproperty("worklog")]     public list<worklog> worklogs { get; set; } } 

and class worklog:

public class worklog : baseentity {     [jsonproperty("updateauthor")]     public string author { get; set; }      [jsonproperty("timespent")]     public string timespent { get; set; }      [jsonproperty("timespentseconds")]     public int timespentseconds { get; set; } } 

i want on output author - sum (timespentseconds)

so need group author , sum.

for each item in issues list make :

var sumtime = issue.fields.worklogs.groupby(x => x.author).select(x => new {     user = x.key.name,     amount = x.sum(s => s.timespentseconds) }); 

which group user , count sum.

but how can manage same not 1 item in list list?

ok, think you're saying can run query single issue, want able run on items in list<issue>.

i'm assuming don't want break out separately issue, i'd this:

list<issue> issues = // issues wherever var sumtime = issues.selectmany(issue => issue.fields.worklogs)                .groupby(x => x.author)                .select( x => new                {                     x.key.name,                      amount = x.sum(s => s.timespentseconds)                }                ); 

disclaimer:

this done entirely memory, no testing.