public void RunDemo()
{
IEnumerable <Singer> singers = DemoCollections.GetSingers();
Singer singer = singers.FirstOrDefault(s => s.Id == 100);
Console.WriteLine(singer == null ? "No such singer" : singer.LastName);
}
private void RunSecondPrototype()
{
IEnumerable <Singer> singers = DemoCollections.GetSingers();
IEnumerable <Concert> concerts = DemoCollections.GetConcerts();
SingerGenderComparer comparer = new SingerGenderComparer();
IEnumerable <IGrouping <int, Concert> > concertGroups = concerts.GroupBy(c => c.SingerId, comparer);
foreach (IGrouping <int, Concert> concertGroup in concertGroups)
{
Console.WriteLine("Concerts of {0} singers: ", comparer.IsPerformedByFemaleSinger(concertGroup.Key) ? "female" : "male");
foreach (Concert concert in concertGroup)
{
Console.WriteLine("Number of concerts: {0}, in the year of {1} by singer {2}.", concert.ConcertCount, concert.Year, concert.SingerId);
}
}
IEnumerable <IGrouping <int, int> > concertGroupsFiltered = concerts.GroupBy(c => c.SingerId, c => c.ConcertCount, comparer);
foreach (IGrouping <int, int> concertGroup in concertGroupsFiltered)
{
Console.WriteLine("Concerts of {0} singers: ", comparer.IsPerformedByFemaleSinger(concertGroup.Key) ? "female" : "male");
foreach (int concertCount in concertGroup)
{
Console.WriteLine("Number of concerts: {0}.", concertCount);
}
}
}
private void RunFirstPrototype()
{
IEnumerable <Singer> singers = DemoCollections.GetSingers();
IEnumerable <Concert> concerts = DemoCollections.GetConcerts();
IEnumerable <IGrouping <int, Concert> > concertGroups = concerts.GroupBy(c => c.SingerId);
foreach (IGrouping <int, Concert> concertGroup in concertGroups)
{
Console.WriteLine("Concerts for singer of ID {0}:", concertGroup.Key);
foreach (Concert concert in concertGroup)
{
Console.WriteLine("Number of concerts: {0}, in the year of {1}.", concert.ConcertCount, concert.Year);
}
}
IEnumerable <IGrouping <int, int> > concertGroupsFiltered = concerts.GroupBy(c => c.SingerId, c => c.ConcertCount);
foreach (IGrouping <int, int> concertGroup in concertGroupsFiltered)
{
Console.WriteLine("Concerts for singer of ID {0}:", concertGroup.Key);
foreach (int concertCount in concertGroup)
{
Console.WriteLine("Number of concerts: {0}.", concertCount);
}
}
}
public void RunDemo()
{
IEnumerable <Singer> singers = DemoCollections.GetSingers();
Dictionary <int, Singer> singersDictionary = singers.ToDictionary(s => s.Id);
Console.WriteLine(singersDictionary[2].FirstName);
Dictionary <int, string> singersDictionaryNames =
singers.ToDictionary(s => s.Id, si => string.Format("Last name: {0}", si.LastName));
Console.WriteLine(singersDictionaryNames[2]);
}
public void RunSelectManyOperatorExampleComplex()
{
IEnumerable <Singer> singers = DemoCollections.GetSingers();
IEnumerable <Concert> concerts = DemoCollections.GetConcerts();
var singerConcerts = singers.SelectMany(s => concerts.Where(c => c.SingerId == s.Id)
.Select(c => new { Year = c.Year, ConcertCount = c.ConcertCount, Name = string.Concat(s.FirstName, " ", s.LastName) }));
foreach (var item in singerConcerts)
{
Console.WriteLine(string.Concat(item.Name, ", ", item.Year, ", ", item.ConcertCount));
}
}
public void RunDemo()
{
string[] bands = DemoCollections.GetBands();
string[] bandsTwo = DemoCollections.GetBands();
bool equal = bands.SequenceEqual(bandsTwo);
Console.WriteLine(equal);
IEnumerable <Singer> singers = DemoCollections.GetSingers();
IEnumerable <Singer> singersTwo = DemoCollections.GetSingers();
bool singersEqual = singers.SequenceEqual(singersTwo, new DefaultSingerComparer());
Console.WriteLine(singersEqual);
}
public void RunDemo()
{
IEnumerable <Singer> singers = DemoCollections.GetSingers();
IEnumerable <Concert> concerts = DemoCollections.GetConcerts();
var singerConcerts = singers.Join(concerts, s => s.Id, c => c.SingerId, (s, c) => new
{
Id = s.Id,
SingerName = string.Concat(s.FirstName, " ", s.LastName),
ConcertCount = c.ConcertCount,
Year = c.Year
});
foreach (var res in singerConcerts)
{
Console.WriteLine(string.Concat(res.Id, ": ", res.SingerName, ", ", res.Year, ", ", res.ConcertCount));
}
}
public void RunDemo()
{
IEnumerable <Singer> singers = DemoCollections.GetSingers();
ILookup <int, Singer> singersByBirthYear = singers.ToLookup(s => s.BirthYear);
IEnumerable <Singer> filtered = singersByBirthYear[1964];
foreach (Singer s in filtered)
{
Console.WriteLine(s.LastName);
}
ILookup <int, string> singerNamesByBirthYear = singers.ToLookup(s => s.BirthYear, si => string.Concat(si.LastName, ", ", si.FirstName));
IEnumerable <string> filtered2 = singerNamesByBirthYear[1964];
foreach (string s in filtered2)
{
Console.WriteLine(s);
}
}
public void RunDemo()
{
List <int> integers = new List <int>()
{
54, 23, 76, 123, 93, 7, 3489
};
int intMin = integers.Min();
string[] bands = { "ACDC", "Queen", "Aerosmith", "Iron Maiden", "Megadeth", "Metallica", "Cream", "Oasis", "Abba", "Blur"
, "Chic", "Eurythmics", "Genesis", "INXS", "Midnight Oil", "Kent", "Madness", "Manic Street Preachers"
, "Noir Desir", "The Offspring", "Pink Floyd", "Rammstein", "Red Hot Chili Peppers", "Tears for Fears"
, "Deep Purple", "KISS" };
string stringMin = bands.Min();
IEnumerable <Singer> singers = DemoCollections.GetSingers();
int minSingerBirthYear = singers.Min(s => s.BirthYear);
String minSingerName = singers.Min(s => s.FirstName);
}
public void RunDemo()
{
string[] bands = { "ACDC", "Queen", "Aerosmith", "Iron Maiden", "Megadeth", "Metallica", "Cream", "Oasis"
, "Abba", "Blur", "Chic", "Eurythmics", "Genesis", "INXS", "Midnight Oil","Kent", "Madness", "Manic Street Preachers"
, "Noir Desir", "The Offspring", "Pink Floyd", "Rammstein", "Red Hot Chili Peppers", "Tears for Fears"
, "Deep Purple", "KISS" };
bool contains = bands.Contains("Queen");
Console.WriteLine(contains);
IEnumerable <Singer> singers = DemoCollections.GetSingers();
Singer s = new Singer()
{
Id = 2, FirstName = "Elvis", LastName = "Presley", BirthYear = 1954
};
bool containsSinger = singers.Contains(s, new DefaultSingerComparer());
Console.WriteLine(containsSinger);
}
public void RunDemo()
{
string[] bands = DemoCollections.GetBands();
IEnumerable <string> bandsDuplicated = bands.Concat(bands);
IEnumerable <string> uniqueBands = bandsDuplicated.Distinct();
foreach (String unique in uniqueBands)
{
Console.WriteLine(unique);
}
IEnumerable <Singer> singers = DemoCollections.GetSingers();
IEnumerable <Singer> singersDuplicates = singers.Concat(singers);
IEnumerable <Singer> uniqueSingers = singersDuplicates.Distinct(new DefaultSingerComparer());
foreach (Singer singer in uniqueSingers)
{
Console.WriteLine(singer.Id);
}
}