Enumerable.ToDictionary 메서드
정의
IEnumerable<T>에서 Dictionary<TKey,TValue>을 만듭니다.Creates a Dictionary<TKey,TValue> from an IEnumerable<T>.
오버로드
ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)
지정된 키 선택기와 요소 선택기 함수에 따라 Dictionary<TKey,TValue>을 사용하여 IEnumerable<T>를 만듭니다.Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to specified key selector and element selector functions.
public:
generic <typename TSource, typename TKey, typename TElement>
[System::Runtime::CompilerServices::Extension]
static System::Collections::Generic::Dictionary<TKey, TElement> ^ ToDictionary(System::Collections::Generic::IEnumerable<TSource> ^ source, Func<TSource, TKey> ^ keySelector, Func<TSource, TElement> ^ elementSelector);
public static System.Collections.Generic.Dictionary<TKey,TElement> ToDictionary<TSource,TKey,TElement> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector);
static member ToDictionary : seq<'Source> * Func<'Source, 'Key> * Func<'Source, 'Element> -> System.Collections.Generic.Dictionary<'Key, 'Element>
<Extension()>
Public Function ToDictionary(Of TSource, TKey, TElement) (source As IEnumerable(Of TSource), keySelector As Func(Of TSource, TKey), elementSelector As Func(Of TSource, TElement)) As Dictionary(Of TKey, TElement)
형식 매개 변수
- TSource
source
요소의 형식입니다.The type of the elements of source
.
- TKey
keySelector
에서 반환하는 키의 형식입니다.The type of the key returned by keySelector
.
- TElement
elementSelector
에서 반환하는 값의 형식입니다.The type of the value returned by elementSelector
.
매개 변수
- source
- IEnumerable<TSource>
Dictionary<TKey,TValue>을 만들기 위한 IEnumerable<T>입니다.An IEnumerable<T> to create a Dictionary<TKey,TValue> from.
- keySelector
- Func<TSource,TKey>
각 요소에서 키를 추출하는 함수입니다.A function to extract a key from each element.
- elementSelector
- Func<TSource,TElement>
각 요소를 사용하여 결과 요소 값을 생성할 변형 함수입니다.A transform function to produce a result element value from each element.
반환
- Dictionary<TKey,TElement>
입력 시퀀스에서 선택한 TElement
형식 값이 포함된 Dictionary<TKey,TValue>입니다.A Dictionary<TKey,TValue> that contains values of type TElement
selected from the input sequence.
예외
source
, keySelector
또는 elementSelector
가 null
인 경우source
or keySelector
or elementSelector
is null
.
또는-or-
keySelector
가 생성하는 키가 null
인 경우keySelector
produces a key that is null
.
keySelector
가 두 요소에 대해 중복된 키를 생성하는 경우keySelector
produces duplicate keys for two elements.
설명
ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)메서드는 기본 같음 비교자를 사용 하 여 Default 키를 비교 합니다.The ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>) method uses the default equality comparer Default to compare keys.
적용 대상
ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)
지정된 키 선택기 함수, 비교자 및 요소 선택기 함수에 따라 Dictionary<TKey,TValue>을 사용하여 IEnumerable<T>를 만듭니다.Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function, a comparer, and an element selector function.
public:
generic <typename TSource, typename TKey, typename TElement>
[System::Runtime::CompilerServices::Extension]
static System::Collections::Generic::Dictionary<TKey, TElement> ^ ToDictionary(System::Collections::Generic::IEnumerable<TSource> ^ source, Func<TSource, TKey> ^ keySelector, Func<TSource, TElement> ^ elementSelector, System::Collections::Generic::IEqualityComparer<TKey> ^ comparer);
public static System.Collections.Generic.Dictionary<TKey,TElement> ToDictionary<TSource,TKey,TElement> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector, System.Collections.Generic.IEqualityComparer<TKey> comparer);
public static System.Collections.Generic.Dictionary<TKey,TElement> ToDictionary<TSource,TKey,TElement> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer);
static member ToDictionary : seq<'Source> * Func<'Source, 'Key> * Func<'Source, 'Element> * System.Collections.Generic.IEqualityComparer<'Key> -> System.Collections.Generic.Dictionary<'Key, 'Element>
<Extension()>
Public Function ToDictionary(Of TSource, TKey, TElement) (source As IEnumerable(Of TSource), keySelector As Func(Of TSource, TKey), elementSelector As Func(Of TSource, TElement), comparer As IEqualityComparer(Of TKey)) As Dictionary(Of TKey, TElement)
형식 매개 변수
- TSource
source
요소의 형식입니다.The type of the elements of source
.
- TKey
keySelector
에서 반환하는 키의 형식입니다.The type of the key returned by keySelector
.
- TElement
elementSelector
에서 반환하는 값의 형식입니다.The type of the value returned by elementSelector
.
매개 변수
- source
- IEnumerable<TSource>
Dictionary<TKey,TValue>을 만들기 위한 IEnumerable<T>입니다.An IEnumerable<T> to create a Dictionary<TKey,TValue> from.
- keySelector
- Func<TSource,TKey>
각 요소에서 키를 추출하는 함수입니다.A function to extract a key from each element.
- elementSelector
- Func<TSource,TElement>
각 요소를 사용하여 결과 요소 값을 생성할 변형 함수입니다.A transform function to produce a result element value from each element.
- comparer
- IEqualityComparer<TKey>
키를 비교할 IEqualityComparer<T>입니다.An IEqualityComparer<T> to compare keys.
반환
- Dictionary<TKey,TElement>
입력 시퀀스에서 선택한 TElement
형식 값이 포함된 Dictionary<TKey,TValue>입니다.A Dictionary<TKey,TValue> that contains values of type TElement
selected from the input sequence.
예외
source
, keySelector
또는 elementSelector
가 null
인 경우source
or keySelector
or elementSelector
is null
.
또는-or-
keySelector
가 생성하는 키가 null
인 경우keySelector
produces a key that is null
.
keySelector
가 두 요소에 대해 중복된 키를 생성하는 경우keySelector
produces duplicate keys for two elements.
설명
comparer
가 이면 null
기본 같음 비교자를 Default 사용 하 여 키를 비교 합니다.If comparer
is null
, the default equality comparer Default is used to compare keys.
적용 대상
ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)
지정된 키 선택기 함수에 따라 Dictionary<TKey,TValue>을 사용하여 IEnumerable<T>를 만듭니다.Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function.
public:
generic <typename TSource, typename TKey>
[System::Runtime::CompilerServices::Extension]
static System::Collections::Generic::Dictionary<TKey, TSource> ^ ToDictionary(System::Collections::Generic::IEnumerable<TSource> ^ source, Func<TSource, TKey> ^ keySelector);
public static System.Collections.Generic.Dictionary<TKey,TSource> ToDictionary<TSource,TKey> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,TKey> keySelector);
static member ToDictionary : seq<'Source> * Func<'Source, 'Key> -> System.Collections.Generic.Dictionary<'Key, 'Source>
<Extension()>
Public Function ToDictionary(Of TSource, TKey) (source As IEnumerable(Of TSource), keySelector As Func(Of TSource, TKey)) As Dictionary(Of TKey, TSource)
형식 매개 변수
- TSource
source
요소의 형식입니다.The type of the elements of source
.
- TKey
keySelector
에서 반환하는 키의 형식입니다.The type of the key returned by keySelector
.
매개 변수
- source
- IEnumerable<TSource>
Dictionary<TKey,TValue>을 만들기 위한 IEnumerable<T>입니다.An IEnumerable<T> to create a Dictionary<TKey,TValue> from.
- keySelector
- Func<TSource,TKey>
각 요소에서 키를 추출하는 함수입니다.A function to extract a key from each element.
반환
- Dictionary<TKey,TSource>
키와 값이 들어 있는 Dictionary<TKey,TValue>입니다.A Dictionary<TKey,TValue> that contains keys and values. 각 그룹의 값은 source
의 순서와 동일합니다.The values within each group are in the same order as in source
.
예외
source
또는 keySelector
가 null
인 경우source
or keySelector
is null
.
또는-or-
keySelector
가 생성하는 키가 null
인 경우keySelector
produces a key that is null
.
keySelector
가 두 요소에 대해 중복된 키를 생성하는 경우keySelector
produces duplicate keys for two elements.
예제
다음 코드 예제에서는를 사용 하 여 ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>) Dictionary<TKey,TValue> 키 선택기를 사용 하 여를 만드는 방법을 보여 줍니다.The following code example demonstrates how to use ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>) to create a Dictionary<TKey,TValue> by using a key selector.
class Package
{
public string Company { get; set; }
public double Weight { get; set; }
public long TrackingNumber { get; set; }
}
public static void ToDictionaryEx1()
{
List<Package> packages =
new List<Package>
{ new Package { Company = "Coho Vineyard", Weight = 25.2, TrackingNumber = 89453312L },
new Package { Company = "Lucerne Publishing", Weight = 18.7, TrackingNumber = 89112755L },
new Package { Company = "Wingtip Toys", Weight = 6.0, TrackingNumber = 299456122L },
new Package { Company = "Adventure Works", Weight = 33.8, TrackingNumber = 4665518773L } };
// Create a Dictionary of Package objects,
// using TrackingNumber as the key.
Dictionary<long, Package> dictionary =
packages.ToDictionary(p => p.TrackingNumber);
foreach (KeyValuePair<long, Package> kvp in dictionary)
{
Console.WriteLine(
"Key {0}: {1}, {2} pounds",
kvp.Key,
kvp.Value.Company,
kvp.Value.Weight);
}
}
/*
This code produces the following output:
Key 89453312: Coho Vineyard, 25.2 pounds
Key 89112755: Lucerne Publishing, 18.7 pounds
Key 299456122: Wingtip Toys, 6 pounds
Key 4665518773: Adventure Works, 33.8 pounds
*/
Structure Package
Public Company As String
Public Weight As Double
Public TrackingNumber As Long
End Structure
Sub ToDictionaryEx1()
' Create a list of Package values.
Dim packages As New List(Of Package)(New Package() _
{New Package With
{.Company = "Coho Vineyard", .Weight = 25.2, .TrackingNumber = 89453312L},
New Package With
{.Company = "Lucerne Publishing", .Weight = 18.7, .TrackingNumber = 89112755L},
New Package With
{.Company = "Wingtip Toys", .Weight = 6.0, .TrackingNumber = 299456122L},
New Package With
{.Company = "Adventure Works", .Weight = 33.8, .TrackingNumber = 4665518773L}})
' Create a Dictionary that contains Package values,
' using TrackingNumber as the key.
Dim dict As Dictionary(Of Long, Package) =
packages.ToDictionary(Function(p) p.TrackingNumber)
' Display the results.
Dim output As New System.Text.StringBuilder
For Each kvp As KeyValuePair(Of Long, Package) In dict
output.AppendLine("Key " & kvp.Key & ": " &
kvp.Value.Company & ", " &
kvp.Value.Weight & " pounds")
Next
Console.WriteLine(output.ToString())
End Sub
' This code produces the following output:
'
' Key 89453312: Coho Vineyard, 25.2 pounds
' Key 89112755: Lucerne Publishing, 18.7 pounds
' Key 299456122: Wingtip Toys, 6 pounds
' Key 4665518773: Adventure Works, 33.8 pounds
설명
ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)메서드는 기본 같음 비교자를 사용 하 여 Default 키를 비교 합니다.The ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>) method uses the default equality comparer Default to compare keys.
적용 대상
ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)
지정된 키 선택기 함수와 키 비교자에 따라 Dictionary<TKey,TValue>을 사용하여 IEnumerable<T>를 만듭니다.Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function and key comparer.
public:
generic <typename TSource, typename TKey>
[System::Runtime::CompilerServices::Extension]
static System::Collections::Generic::Dictionary<TKey, TSource> ^ ToDictionary(System::Collections::Generic::IEnumerable<TSource> ^ source, Func<TSource, TKey> ^ keySelector, System::Collections::Generic::IEqualityComparer<TKey> ^ comparer);
public static System.Collections.Generic.Dictionary<TKey,TSource> ToDictionary<TSource,TKey> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,TKey> keySelector, System.Collections.Generic.IEqualityComparer<TKey> comparer);
public static System.Collections.Generic.Dictionary<TKey,TSource> ToDictionary<TSource,TKey> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,TKey> keySelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer);
static member ToDictionary : seq<'Source> * Func<'Source, 'Key> * System.Collections.Generic.IEqualityComparer<'Key> -> System.Collections.Generic.Dictionary<'Key, 'Source>
<Extension()>
Public Function ToDictionary(Of TSource, TKey) (source As IEnumerable(Of TSource), keySelector As Func(Of TSource, TKey), comparer As IEqualityComparer(Of TKey)) As Dictionary(Of TKey, TSource)
형식 매개 변수
- TSource
source
요소의 형식입니다.The type of the elements of source
.
- TKey
keySelector
에서 반환하는 키의 형식입니다.The type of the keys returned by keySelector
.
매개 변수
- source
- IEnumerable<TSource>
Dictionary<TKey,TValue>을 만들기 위한 IEnumerable<T>입니다.An IEnumerable<T> to create a Dictionary<TKey,TValue> from.
- keySelector
- Func<TSource,TKey>
각 요소에서 키를 추출하는 함수입니다.A function to extract a key from each element.
- comparer
- IEqualityComparer<TKey>
키를 비교할 IEqualityComparer<T>입니다.An IEqualityComparer<T> to compare keys.
반환
- Dictionary<TKey,TSource>
키와 값이 들어 있는 Dictionary<TKey,TValue>입니다.A Dictionary<TKey,TValue> that contains keys and values. 각 그룹의 값은 source
의 순서와 동일합니다.The values within each group are in the same order as in source
.
예외
source
또는 keySelector
가 null
인 경우source
or keySelector
is null
.
또는-or-
keySelector
가 생성하는 키가 null
인 경우keySelector
produces a key that is null
.
keySelector
가 두 요소에 대해 중복된 키를 생성하는 경우keySelector
produces duplicate keys for two elements.
설명
comparer
가 이면 null
기본 같음 비교자를 Default 사용 하 여 키를 비교 합니다.If comparer
is null
, the default equality comparer Default is used to compare keys.