Enumerable.LongCount Enumerable.LongCount Enumerable.LongCount Enumerable.LongCount Method

Definición

Devuelve un valor Int64 que representa el número de elementos de una secuencia.Returns an Int64 that represents the number of elements in a sequence.

Sobrecargas

LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Devuelve un valor Int64 que representa el número de elementos de una secuencia que satisfacen una condición.Returns an Int64 that represents how many elements in a sequence satisfy a condition.

LongCount<TSource>(IEnumerable<TSource>) LongCount<TSource>(IEnumerable<TSource>) LongCount<TSource>(IEnumerable<TSource>) LongCount<TSource>(IEnumerable<TSource>)

Devuelve un valor Int64 que representa el número total de elementos de una secuencia.Returns an Int64 that represents the total number of elements in a sequence.

LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Devuelve un valor Int64 que representa el número de elementos de una secuencia que satisfacen una condición.Returns an Int64 that represents how many elements in a sequence satisfy a condition.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static long LongCount(System::Collections::Generic::IEnumerable<TSource> ^ source, Func<TSource, bool> ^ predicate);
public static long LongCount<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,bool> predicate);
static member LongCount : seq<'Source> * Func<'Source, bool> -> int64
<Extension()>
Public Function LongCount(Of TSource) (source As IEnumerable(Of TSource), predicate As Func(Of TSource, Boolean)) As Long

Parámetros de tipo

TSource

Tipo de los elementos de source.The type of the elements of source.

Parámetros

source
IEnumerable<TSource>

IEnumerable<T> que contiene los elementos que se van a contar.An IEnumerable<T> that contains the elements to be counted.

predicate
Func<TSource,Boolean>

Función para probar cada elemento de una condición.A function to test each element for a condition.

Devoluciones

Un número que representa cuántos elementos de la secuencia especificada satisfacen la condición de la función de predicado.A number that represents how many elements in the sequence satisfy the condition in the predicate function.

Excepciones

source o predicate es null.source or predicate is null.

El número de elementos que coinciden es superior a MaxValue.The number of matching elements exceeds MaxValue.

Ejemplos

En el ejemplo de código siguiente se muestra LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) cómo usar para contar los elementos de una matriz que satisfacen una condición.The following code example demonstrates how to use LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) to count the elements in an array that satisfy a condition.

class Pet
{
    public string Name { get; set; }
    public int Age { get; set; }
}

public static void LongCountEx2()
{
    Pet[] pets = { new Pet { Name="Barley", Age=8 },
                   new Pet { Name="Boots", Age=4 },
                   new Pet { Name="Whiskers", Age=1 } };

    const int Age = 3;

    long count = pets.LongCount(pet => pet.Age > Age);

    Console.WriteLine("There are {0} animals over age {1}.", count, Age);
}

/*
 This code produces the following output:

 There are 2 animals over age 3.
*/
Structure Pet
    Public Name As String
    Public Age As Integer
End Structure

Sub LongCountEx2()
    ' Create a list of Pet objects.
    Dim pets As New List(Of Pet)(New Pet() _
                 {New Pet With {.Name = "Barley", .Age = 8},
                  New Pet With {.Name = "Boots", .Age = 4},
                  New Pet With {.Name = "Whiskers", .Age = 1}})

    ' Determine the number of elements in the list
    ' where the pet's age is greater than a constant value (3).
    Const Age As Integer = 3
    Dim count As Long =
pets.LongCount(Function(pet) pet.Age > Age)

    ' Display the result.
    MsgBox("There are " & count & " animals over age " & Age)
End Sub

' This code produces the following output:
'
' There are 2 animals over age 3

Comentarios

Utilice este método en lugar Count de cuando espera que el resultado sea mayor que MaxValue.Use this method rather than Count when you expect the result to be greater than MaxValue.

En Visual Basic sintaxis de expresiones de consulta Aggregate Into LongCount() , una cláusula se convierte en una invocación LongCountde.In Visual Basic query expression syntax, an Aggregate Into LongCount() clause translates to an invocation of LongCount.

Consulte también:

LongCount<TSource>(IEnumerable<TSource>) LongCount<TSource>(IEnumerable<TSource>) LongCount<TSource>(IEnumerable<TSource>) LongCount<TSource>(IEnumerable<TSource>)

Devuelve un valor Int64 que representa el número total de elementos de una secuencia.Returns an Int64 that represents the total number of elements in a sequence.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static long LongCount(System::Collections::Generic::IEnumerable<TSource> ^ source);
public static long LongCount<TSource> (this System.Collections.Generic.IEnumerable<TSource> source);
static member LongCount : seq<'Source> -> int64
<Extension()>
Public Function LongCount(Of TSource) (source As IEnumerable(Of TSource)) As Long

Parámetros de tipo

TSource

Tipo de los elementos de source.The type of the elements of source.

Parámetros

source
IEnumerable<TSource>

IEnumerable<T> que contiene los elementos que se van a contar.An IEnumerable<T> that contains the elements to be counted.

Devoluciones

El número de elementos de la secuencia de origen.The number of elements in the source sequence.

Excepciones

El número de elementos es superior a MaxValue.The number of elements exceeds MaxValue.

Ejemplos

En el ejemplo de código siguiente se muestra LongCount<TSource>(IEnumerable<TSource>) cómo usar para contar los elementos de una matriz.The following code example demonstrates how to use LongCount<TSource>(IEnumerable<TSource>) to count the elements in an array.

string[] fruits = { "apple", "banana", "mango", 
                      "orange", "passionfruit", "grape" };

long count = fruits.LongCount();

Console.WriteLine("There are {0} fruits in the collection.", count);

/*
 This code produces the following output:

 There are 6 fruits in the collection.
*/
' Create an array of strings.
Dim fruits() As String =
{"apple", "banana", "mango", "orange", "passionfruit", "grape"}

' Get the number of items in the array.
Dim count As Long = fruits.LongCount()

' Display the result.
MsgBox("There are " & count & " fruits in the collection.")

' This code produces the following output:
'
' There are 6 fruits in the collection.

Comentarios

Utilice este método en lugar Count de cuando espera que el resultado sea mayor que MaxValue.Use this method rather than Count when you expect the result to be greater than MaxValue.

En Visual Basic sintaxis de expresiones de consulta Aggregate Into LongCount() , una cláusula se convierte en una invocación LongCountde.In Visual Basic query expression syntax, an Aggregate Into LongCount() clause translates to an invocation of LongCount.

Consulte también:

Se aplica a