Queryable.Concat<TSource>(IQueryable<TSource>, IEnumerable<TSource>) Método

Definición

Concatena dos secuencias.Concatenates two sequences.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::IQueryable<TSource> ^ Concat(System::Linq::IQueryable<TSource> ^ source1, System::Collections::Generic::IEnumerable<TSource> ^ source2);
public static System.Linq.IQueryable<TSource> Concat<TSource> (this System.Linq.IQueryable<TSource> source1, System.Collections.Generic.IEnumerable<TSource> source2);
static member Concat : System.Linq.IQueryable<'Source> * seq<'Source> -> System.Linq.IQueryable<'Source>
<Extension()>
Public Function Concat(Of TSource) (source1 As IQueryable(Of TSource), source2 As IEnumerable(Of TSource)) As IQueryable(Of TSource)

Parámetros de tipo

TSource

Tipo de los elementos de las secuencias de entrada.The type of the elements of the input sequences.

Parámetros

source1
IQueryable<TSource>

Primera secuencia que se va a concatenar.The first sequence to concatenate.

source2
IEnumerable<TSource>

Secuencia que se va a concatenar con la primera secuencia.The sequence to concatenate to the first sequence.

Devoluciones

IQueryable<TSource>

IQueryable<T> que contiene los elementos concatenados de las dos secuencias de entrada.An IQueryable<T> that contains the concatenated elements of the two input sequences.

Excepciones

source1 o source2 es null.source1 or source2 is null.

Ejemplos

En el ejemplo de código siguiente se muestra Concat<TSource>(IQueryable<TSource>, IEnumerable<TSource>) cómo usar para concatenar dos secuencias.The following code example demonstrates how to use Concat<TSource>(IQueryable<TSource>, IEnumerable<TSource>) to concatenate two sequences.

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

// This method creates and returns an array of Pet objects.
static Pet[] GetCats()
{
    Pet[] cats = { new Pet { Name="Barley", Age=8 },
                   new Pet { Name="Boots", Age=4 },
                   new Pet { Name="Whiskers", Age=1 } };
    return cats;
}

// This method creates and returns an array of Pet objects.
static Pet[] GetDogs()
{
    Pet[] dogs = { new Pet { Name="Bounder", Age=3 },
                   new Pet { Name="Snoopy", Age=14 },
                   new Pet { Name="Fido", Age=9 } };
    return dogs;
}

public static void ConcatEx1()
{
    Pet[] cats = GetCats();
    Pet[] dogs = GetDogs();

    // Concatenate a collection of cat names to a
    // collection of dog names by using Concat().
    IEnumerable<string> query =
        cats.AsQueryable()
        .Select(cat => cat.Name)
        .Concat(dogs.Select(dog => dog.Name));

    foreach (string name in query)
        Console.WriteLine(name);
}

// This code produces the following output:
//
// Barley
// Boots
// Whiskers
// Bounder
// Snoopy
// Fido


' This method creates and returns an array of Pet objects.
Shared Function GetCats() As Pet()
    Dim cats() As Pet = _
        {New Pet With {.Name = "Barley", .Age = 8}, _
         New Pet With {.Name = "Boots", .Age = 4}, _
         New Pet With {.Name = "Whiskers", .Age = 1}}

    Return cats
End Function

' This method creates and returns an array of Pet objects.
Shared Function GetDogs() As Pet()
    Dim dogs() As Pet = _
        {New Pet With {.Name = "Bounder", .Age = 3}, _
         New Pet With {.Name = "Snoopy", .Age = 14}, _
         New Pet With {.Name = "Fido", .Age = 9}}

    Return dogs
End Function

Shared Sub ConcatEx1()
    Dim cats() As Pet = GetCats()
    Dim dogs() As Pet = GetDogs()

    ' Concatenate a collection of cat names to a
    ' collection of dog names by using Concat().
    Dim query As IEnumerable(Of String) = _
        cats.AsQueryable() _
        .Select(Function(cat) cat.Name) _
        .Concat(dogs.Select(Function(dog) dog.Name))

    For Each name As String In query
        MsgBox(name)
    Next
End Sub

Structure Pet
    Dim Name As String
    Dim Age As Integer
End Structure

' This code produces the following output:
'
' Barley
' Boots
' Whiskers
' Bounder
' Snoopy
' Fido

Comentarios

El Concat<TSource>(IQueryable<TSource>, IEnumerable<TSource>) método genera un MethodCallExpression que representa la Concat<TSource>(IQueryable<TSource>, IEnumerable<TSource>) llamada a sí mismo como un método genérico construido.The Concat<TSource>(IQueryable<TSource>, IEnumerable<TSource>) method generates a MethodCallExpression that represents calling Concat<TSource>(IQueryable<TSource>, IEnumerable<TSource>) itself as a constructed generic method. A continuación, pasa MethodCallExpression el CreateQuery<TElement>(Expression) al método de IQueryProvider representado por la Provider propiedad del source1 parámetro.It then passes the MethodCallExpression to the CreateQuery<TElement>(Expression) method of the IQueryProvider represented by the Provider property of the source1 parameter.

El comportamiento de la consulta que se produce como resultado de ejecutar un árbol de expresión que Concat<TSource>(IQueryable<TSource>, IEnumerable<TSource>) representa la llamada depende de la implementación del tipo source1 del parámetro.The query behavior that occurs as a result of executing an expression tree that represents calling Concat<TSource>(IQueryable<TSource>, IEnumerable<TSource>) depends on the implementation of the type of the source1 parameter. El comportamiento esperado es que los elementos de source2 se concatenan con los de source1 para crear una nueva secuencia.The expected behavior is that the elements in source2 are concatenated to those of source1 to create a new sequence.

Se aplica a