public static Dictionary <TKey, TElement> ToDictionary <T, TKey, TElement>(
[InstantHandle] this IEnumerable <T> source,
[InstantHandle] Func <T, TKey> keySelector,
[InstantHandle] Func <T, TElement> elementSelector,
IEqualityComparer <TKey>?comparer,
DictionaryDuplicate duplicateHandling)
where TKey : notnull
{
Code.NotNull(source, nameof(source));
Code.NotNull(keySelector, nameof(keySelector));
Code.NotNull(elementSelector, nameof(elementSelector));
Code.InRange(
(int)duplicateHandling, nameof(duplicateHandling), (int)DictionaryDuplicate.Throw, (int)DictionaryDuplicate.LastWins);
if (duplicateHandling == DictionaryDuplicate.Throw)
{
return(source.ToDictionary(keySelector, elementSelector, comparer));
}
var result = new Dictionary <TKey, TElement>(comparer);
foreach (var item in source)
{
var key = keySelector(item);
if (duplicateHandling == DictionaryDuplicate.LastWins || !result.ContainsKey(key))
{
result[key] = elementSelector(item);
}
}
return(result);
}
public static Dictionary <TKey, TElement> ToDictionary <T, TKey, TElement>(
[InstantHandle] this IEnumerable <T> source,
[InstantHandle] Func <T, TKey> keySelector,
[InstantHandle] Func <T, TElement> elementSelector,
DictionaryDuplicate duplicateHandling)
where TKey : notnull =>
ToDictionary(source, keySelector, elementSelector, null, duplicateHandling);
public static Dictionary <TKey, T> ToDictionary <T, TKey>(
[InstantHandle] this IEnumerable <T> source,
[InstantHandle] Func <T, TKey> keySelector,
IEqualityComparer <TKey>?comparer,
DictionaryDuplicate duplicateHandling)
where TKey : notnull =>
ToDictionary(source, keySelector, Fn <T> .Self, comparer, duplicateHandling);
public static Dictionary <TKey, T> ToDictionary <T, TKey>(
[NotNull, InstantHandle] this IEnumerable <T> source,
[NotNull, InstantHandle] Func <T, TKey> keySelector,
[CanBeNull] IEqualityComparer <TKey> comparer,
DictionaryDuplicate duplicateHandling) =>
ToDictionary(source, keySelector, Fn <T> .Self, comparer, duplicateHandling);
public static Dictionary <TKey, T> ToDictionary <T, TKey>(
[NotNull, InstantHandle] this IEnumerable <T> source,
[NotNull, InstantHandle] Func <T, TKey> keySelector,
DictionaryDuplicate duplicateHandling) =>
ToDictionary(source, keySelector, Fn <T> .Self, null, duplicateHandling);
public static Dictionary <TKey, TElement> ToDictionary <T, TKey, TElement>(
[NotNull] this IEnumerable <T> source,
[NotNull] Func <T, TKey> keySelector,
[NotNull] Func <T, TElement> elementSelector,
DictionaryDuplicate duplicateHandling) =>
ToDictionary(source, keySelector, elementSelector, null, duplicateHandling);
