C# Language
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C# Language LINQ Queries GroupBy one or multiple fields
Example
Lets assume we have some Film model:
public class Film {
public string Title { get; set; }
public string Category { get; set; }
public int Year { get; set; }
}
Group by Category property:
foreach (var grp in films.GroupBy(f => f.Category)) {
var groupCategory = grp.Key;
var numberOfFilmsInCategory = grp.Count();
}
Group by Category and Year:
foreach (var grp in films.GroupBy(f => new { Category = f.Category, Year = f.Year })) {
var groupCategory = grp.Key.Category;
var groupYear = grp.Key.Year;
var numberOfFilmsInCategory = grp.Count();
}
