Enumerable.ToDictionary Método
Definición
Crea un Dictionary<TKey,TValue> a partir de un IEnumerable<T>.Creates a Dictionary<TKey,TValue> from an IEnumerable<T>.
Sobrecargas
ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>) |
Crea un objeto Dictionary<TKey,TValue> a partir de un objeto IEnumerable<T> según el selector de claves especificado y las funciones del selector de elementos.Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to specified key selector and element selector functions. |
ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>) |
Crea un objeto Dictionary<TKey,TValue> a partir de un objeto IEnumerable<T> según una función del selector de claves especificada, un comparador y una función del selector de elementos.Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function, a comparer, and an element selector function. |
ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>) |
Crea una clase Dictionary<TKey,TValue> a partir de una interfaz IEnumerable<T> según una función del selector de claves especificada.Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function. |
ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>) |
Crea un objeto Dictionary<TKey,TValue> a partir de un objeto IEnumerable<T> según una función del selector de claves especificada y el comparador de claves.Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function and key comparer. |
ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)
Crea un objeto Dictionary<TKey,TValue> a partir de un objeto IEnumerable<T> según el selector de claves especificado y las funciones del selector de elementos.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)
Parámetros de tipo
- TSource
Tipo de los elementos de source
.The type of the elements of source
.
- TKey
Tipo de la clave devuelta por keySelector
.The type of the key returned by keySelector
.
- TElement
Tipo de valor devuelto por elementSelector
.The type of the value returned by elementSelector
.
Parámetros
- source
- IEnumerable<TSource>
IEnumerable<T> a partir del que se va a crear un Dictionary<TKey,TValue>.An IEnumerable<T> to create a Dictionary<TKey,TValue> from.
- keySelector
- Func<TSource,TKey>
Función para extraer una clave a partir de cada elemento.A function to extract a key from each element.
- elementSelector
- Func<TSource,TElement>
Función de transformación que va a generar un valor de elemento de resultado a partir de cada elemento.A transform function to produce a result element value from each element.
Devoluciones
- Dictionary<TKey,TElement>
Dictionary<TKey,TValue> que contiene valores de tipo TElement
seleccionados en la secuencia de entrada.A Dictionary<TKey,TValue> that contains values of type TElement
selected from the input sequence.
Excepciones
source
o keySelector
o elementSelector
es null
.source
or keySelector
or elementSelector
is null
.
o bien-or-
keySelector
genera una clave cuyo valor es null
.keySelector
produces a key that is null
.
keySelector
genera claves duplicadas para dos elementos.keySelector
produces duplicate keys for two elements.
Comentarios
El ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>) método utiliza el comparador de igualdad predeterminado Default para comparar las claves.The ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>) method uses the default equality comparer Default to compare keys.
Se aplica a
ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)
Crea un objeto Dictionary<TKey,TValue> a partir de un objeto IEnumerable<T> según una función del selector de claves especificada, un comparador y una función del selector de elementos.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)
Parámetros de tipo
- TSource
Tipo de los elementos de source
.The type of the elements of source
.
- TKey
Tipo de la clave devuelta por keySelector
.The type of the key returned by keySelector
.
- TElement
Tipo de valor devuelto por elementSelector
.The type of the value returned by elementSelector
.
Parámetros
- source
- IEnumerable<TSource>
IEnumerable<T> a partir del que se va a crear un Dictionary<TKey,TValue>.An IEnumerable<T> to create a Dictionary<TKey,TValue> from.
- keySelector
- Func<TSource,TKey>
Función para extraer una clave a partir de cada elemento.A function to extract a key from each element.
- elementSelector
- Func<TSource,TElement>
Función de transformación que va a generar un valor de elemento de resultado a partir de cada elemento.A transform function to produce a result element value from each element.
- comparer
- IEqualityComparer<TKey>
IEqualityComparer<T> para comparar claves.An IEqualityComparer<T> to compare keys.
Devoluciones
- Dictionary<TKey,TElement>
Dictionary<TKey,TValue> que contiene valores de tipo TElement
seleccionados en la secuencia de entrada.A Dictionary<TKey,TValue> that contains values of type TElement
selected from the input sequence.
Excepciones
source
o keySelector
o elementSelector
es null
.source
or keySelector
or elementSelector
is null
.
o bien-or-
keySelector
genera una clave cuyo valor es null
.keySelector
produces a key that is null
.
keySelector
genera claves duplicadas para dos elementos.keySelector
produces duplicate keys for two elements.
Comentarios
Si comparer
es null
, se utiliza el comparador de igualdad predeterminado Default para comparar las claves.If comparer
is null
, the default equality comparer Default is used to compare keys.
Se aplica a
ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)
Crea una clase Dictionary<TKey,TValue> a partir de una interfaz IEnumerable<T> según una función del selector de claves especificada.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)
Parámetros de tipo
- TSource
Tipo de los elementos de source
.The type of the elements of source
.
- TKey
Tipo de la clave devuelta por keySelector
.The type of the key returned by keySelector
.
Parámetros
- source
- IEnumerable<TSource>
IEnumerable<T> a partir del que se va a crear un Dictionary<TKey,TValue>.An IEnumerable<T> to create a Dictionary<TKey,TValue> from.
- keySelector
- Func<TSource,TKey>
Función para extraer una clave a partir de cada elemento.A function to extract a key from each element.
Devoluciones
- Dictionary<TKey,TSource>
Dictionary<TKey,TValue> que contiene claves y valores.A Dictionary<TKey,TValue> that contains keys and values. Los valores de cada grupo están en el mismo orden que en source
.The values within each group are in the same order as in source
.
Excepciones
source
o keySelector
es null
.source
or keySelector
is null
.
o bien-or-
keySelector
genera una clave cuyo valor es null
.keySelector
produces a key that is null
.
keySelector
genera claves duplicadas para dos elementos.keySelector
produces duplicate keys for two elements.
Ejemplos
En el ejemplo de código siguiente se muestra cómo utilizar ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>) para crear un Dictionary<TKey,TValue> mediante un selector de claves.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
Comentarios
El ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>) método utiliza el comparador de igualdad predeterminado Default para comparar las claves.The ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>) method uses the default equality comparer Default to compare keys.
Se aplica a
ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)
Crea un objeto Dictionary<TKey,TValue> a partir de un objeto IEnumerable<T> según una función del selector de claves especificada y el comparador de claves.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)
Parámetros de tipo
- TSource
Tipo de los elementos de source
.The type of the elements of source
.
- TKey
Tipo de las claves devueltas por keySelector
.The type of the keys returned by keySelector
.
Parámetros
- source
- IEnumerable<TSource>
IEnumerable<T> a partir del que se va a crear un Dictionary<TKey,TValue>.An IEnumerable<T> to create a Dictionary<TKey,TValue> from.
- keySelector
- Func<TSource,TKey>
Función para extraer una clave a partir de cada elemento.A function to extract a key from each element.
- comparer
- IEqualityComparer<TKey>
IEqualityComparer<T> para comparar claves.An IEqualityComparer<T> to compare keys.
Devoluciones
- Dictionary<TKey,TSource>
Dictionary<TKey,TValue> que contiene claves y valores.A Dictionary<TKey,TValue> that contains keys and values. Los valores de cada grupo están en el mismo orden que en source
.The values within each group are in the same order as in source
.
Excepciones
source
o keySelector
es null
.source
or keySelector
is null
.
o bien-or-
keySelector
genera una clave cuyo valor es null
.keySelector
produces a key that is null
.
keySelector
genera claves duplicadas para dos elementos.keySelector
produces duplicate keys for two elements.
Comentarios
Si comparer
es null
, se utiliza el comparador de igualdad predeterminado Default para comparar las claves.If comparer
is null
, the default equality comparer Default is used to compare keys.