private void Snippet_LinqSelect(List <Buddy> buddies)
{
IEnumerable <string> namelist = buddies
.Select(buddy => buddy.Name);
ConsoleTools.WriteCollection(namelist);
// [Sylvester, Bogdan, Mark, Robert, Akos, Sergey]
}
private void Snippet_LinqWhere(List <Buddy> buddies)
{
var polishBuddies = buddies
.Where(buddy => buddy.Country == "Poland");
ConsoleTools.WriteCollection(polishBuddies);
// [7=Bogdan (Poland), 2=Robert (Poland)]
}
private void Snippet_LinqDistinct(List <Buddy> buddies)
{
var countries = buddies
.Select(buddy => buddy.Country)
.Distinct();
ConsoleTools.WriteCollection(countries);
// [UK, Poland, Ukraine]
}
private void Snippet_LinqOrderByDescending_ThenBy(List <Buddy> buddies)
{
var buddiesOrdered = buddies
.OrderByDescending(buddy => buddy.Country)
.ThenBy(buddy => buddy.Name);
ConsoleTools.WriteCollection(buddiesOrdered);
// [9=Sergey (Ukraine), 6=Akos (UK), 3=Mark (UK), 1=Sylvester (UK), 7=Bogdan (Poland), 2=Robert (Poland)]
}
public void Run()
{
var buddies = new List <Buddy> {
new Buddy(1, "Sylvester", "UK"),
new Buddy(7, "Bogdan", "Poland", 51000.00m),
new Buddy(3, "Mark", "UK", 65000.00m),
new Buddy(2, "Robert", "Poland", 43000.00m),
new Buddy(6, "Akos", "UK", 49000.00m),
new Buddy(9, "Sergey", "Ukraine", 34000.00m)
};
ConsoleTools.WriteCollection(buddies);
Snippet_LinqSelect(buddies);
Snippet_LinqDistinct(buddies);
Snippet_LinqAggregate(buddies);
Snippet_LinqWhere(buddies);
Snippet_LinqCount(buddies);
Snippet_LinqAll(buddies);
Snippet_LinqSumAvgMax(buddies);
Snippet_LinqOrderByDescending_ThenBy(buddies);
}
private void Snippet_LinqAggregate(List <Buddy> buddies)
{
var buddiesByCountry = buddies
.Aggregate <Buddy, Dictionary <string, int> >(
new Dictionary <string, int>(),
(dict, buddy) =>
{
if (dict.ContainsKey(buddy.Country))
{
dict[buddy.Country] += 1;
}
else
{
dict[buddy.Country] = 1;
}
return(dict);
}
);
var printlist = buddiesByCountry
.Select(pair => $"{pair.Key}={pair.Value}");
ConsoleTools.WriteCollection(printlist);
// [UK=3, Poland=2, Ukraine=1]
}
