Enumerable.Any Metoda

Definice

Určuje, zda kterýkoli prvek sekvence existuje nebo splňuje podmínku.Determines whether any element of a sequence exists or satisfies a condition.

Přetížení

Any<TSource>(IEnumerable<TSource>)

Určuje, zda sekvence obsahuje nějaké prvky.Determines whether a sequence contains any elements.

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

Určuje, zda kterýkoli prvek sekvence splňuje podmínku.Determines whether any element of a sequence satisfies a condition.

Any<TSource>(IEnumerable<TSource>)

Určuje, zda sekvence obsahuje nějaké prvky.Determines whether a sequence contains any elements.

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

Parametry typu

TSource

Typ prvků source .The type of the elements of source.

Parametry

source
IEnumerable<TSource>

Pro IEnumerable<T> kontrolu vyprázdnění.The IEnumerable<T> to check for emptiness.

Návraty

Boolean

true Pokud zdrojová sekvence obsahuje nějaké prvky, v opačném případě false .true if the source sequence contains any elements; otherwise, false.

Výjimky

source je null.source is null.

Příklady

Následující příklad kódu ukazuje, jak použít Any k určení, zda sekvence obsahuje nějaké prvky.The following code example demonstrates how to use Any to determine whether a sequence contains any elements.

List<int> numbers = new List<int> { 1, 2 };
bool hasElements = numbers.Any();

Console.WriteLine("The list {0} empty.",
    hasElements ? "is not" : "is");

// This code produces the following output:
//
// The list is not empty.
' Create a list of Integers.
Dim numbers As New List(Of Integer)(New Integer() {1, 2})

' Determine if the list contains any items.
Dim hasElements As Boolean = numbers.Any()

' Display the output.
Dim text As String = IIf(hasElements, "not ", "")
Console.WriteLine($"The list is {text}empty.")

' This code produces the following output:
'
' The list is not empty.

Logická hodnota, kterou Any<TSource>(IEnumerable<TSource>) Metoda vrátí, se obvykle používá v predikátu where klauzule ( Where klauzule v Visual Basic) nebo přímém volání Where<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) metody.The Boolean value that the Any<TSource>(IEnumerable<TSource>) method returns is typically used in the predicate of a where clause (Where clause in Visual Basic) or a direct call to the Where<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) method. Následující příklad ukazuje toto použití Any metody.The following example demonstrates this use of the Any method.

class Pet
{
    public string Name { get; set; }
    public int Age { get; set; }
}
class Person
{
    public string LastName { get; set; }
    public Pet[] Pets { get; set; }
}

public static void AnyEx2()
{
    List<Person> people = new List<Person>
        { new Person { LastName = "Haas",
                       Pets = new Pet[] { new Pet { Name="Barley", Age=10 },
                                          new Pet { Name="Boots", Age=14 },
                                          new Pet { Name="Whiskers", Age=6 }}},
          new Person { LastName = "Fakhouri",
                       Pets = new Pet[] { new Pet { Name = "Snowball", Age = 1}}},
          new Person { LastName = "Antebi",
                       Pets = new Pet[] { }},
          new Person { LastName = "Philips",
                       Pets = new Pet[] { new Pet { Name = "Sweetie", Age = 2},
                                          new Pet { Name = "Rover", Age = 13}} }
        };

    // Determine which people have a non-empty Pet array.
    IEnumerable<string> names = from person in people
                                where person.Pets.Any()
                                select person.LastName;

    foreach (string name in names)
    {
        Console.WriteLine(name);
    }

    /* This code produces the following output:

       Haas
       Fakhouri
       Philips
    */
}
Structure Pet
    Public Name As String
    Public Age As Integer
End Structure

Structure Person
    Public LastName As String
    Public Pets() As Pet
End Structure

Sub AnyEx2()
    Dim people As New List(Of Person)(New Person() _
{New Person With {.LastName = "Haas",
                  .Pets = New Pet() {New Pet With {.Name = "Barley", .Age = 10},
                                     New Pet With {.Name = "Boots", .Age = 14},
                                     New Pet With {.Name = "Whiskers", .Age = 6}}},
  New Person With {.LastName = "Fakhouri",
                   .Pets = New Pet() {New Pet With {.Name = "Snowball", .Age = 1}}},
  New Person With {.LastName = "Antebi",
                   .Pets = New Pet() {}},
  New Person With {.LastName = "Philips",
                   .Pets = New Pet() {New Pet With {.Name = "Sweetie", .Age = 2},
                                      New Pet With {.Name = "Rover", .Age = 13}}}})

    ' Determine which people have a non-empty Pet array.
    Dim names = From person In people
                Where person.Pets.Any()
                Select person.LastName

    For Each name As String In names
        Console.WriteLine(name)
    Next

    ' This code produces the following output:
    '
    ' Haas
    ' Fakhouri
    ' Philips

End Sub

Poznámky

Poznámka

Tato metoda nevrací žádný z prvků kolekce.This method does not return any one element of a collection. Místo toho určuje, zda kolekce obsahuje nějaké prvky.Instead, it determines whether the collection contains any elements.

Výčet source je zastaven, jakmile lze určit výsledek.The enumeration of source is stopped as soon as the result can be determined.

V Visual Basic syntaxe výrazu dotazu je Aggregate Into Any() klauzule přeložena k vyvolání Any .In Visual Basic query expression syntax, an Aggregate Into Any() clause translates to an invocation of Any.

Viz také

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

Určuje, zda kterýkoli prvek sekvence splňuje podmínku.Determines whether any element of a sequence satisfies a condition.

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

Parametry typu

TSource

Typ prvků source .The type of the elements of source.

Parametry

source
IEnumerable<TSource>

IEnumerable<T>Jejichž prvky pro použití predikátu.An IEnumerable<T> whose elements to apply the predicate to.

predicate
Func<TSource,Boolean>

Funkce pro otestování každého prvku podmínky.A function to test each element for a condition.

Návraty

Boolean

true Pokud není zdrojová sekvence prázdná a nejméně jeden z jeho elementů předá test v zadaném predikátu; v opačném případě false .true if the source sequence is not empty and at least one of its elements passes the test in the specified predicate; otherwise, false.

Výjimky

source nebo predicate je null .source or predicate is null.

Příklady

Následující příklad kódu ukazuje, jak použít Any k určení, zda kterýkoli prvek v sekvenci splňuje podmínku.The following code example demonstrates how to use Any to determine whether any element in a sequence satisfies a condition.

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

public static void AnyEx3()
{
    // Create an array of Pets.
    Pet[] pets =
        { new Pet { Name="Barley", Age=8, Vaccinated=true },
          new Pet { Name="Boots", Age=4, Vaccinated=false },
          new Pet { Name="Whiskers", Age=1, Vaccinated=false } };

    // Determine whether any pets over age 1 are also unvaccinated.
    bool unvaccinated =
        pets.Any(p => p.Age > 1 && p.Vaccinated == false);

    Console.WriteLine(
        "There {0} unvaccinated animals over age one.",
        unvaccinated ? "are" : "are not any");
}

// This code produces the following output:
//
//  There are unvaccinated animals over age one.
Structure Pet
    Public Name As String
    Public Age As Integer
    Public Vaccinated As Boolean
End Structure

Shared Sub AnyEx3()
    ' Create a list of Pets
    Dim pets As New List(Of Pet)(New Pet() _
                         {New Pet With {.Name = "Barley", .Age = 8, .Vaccinated = True},
                          New Pet With {.Name = "Boots", .Age = 4, .Vaccinated = False},
                          New Pet With {.Name = "Whiskers", .Age = 1, .Vaccinated = False}})

    ' Determine whether any pets over age 1 are also unvaccinated.
    Dim unvaccinated As Boolean =
pets.Any(Function(pet) pet.Age > 1 And pet.Vaccinated = False)

    ' Display the output.
    Dim text As String = IIf(unvaccinated, "are", "are not")
    Console.WriteLine($"There {text} unvaccinated animals over age 1.")
End Sub

' This code produces the following output:
'
' There are unvaccinated animals over age 1.

Poznámky

Poznámka

Tato metoda nevrací žádný z prvků kolekce.This method does not return any one element of a collection. Místo toho určuje, zda některé prvky kolekce splní podmínku.Instead, it determines whether any elements of a collection satisfy a condition.

Výčet source je zastaven, jakmile lze určit výsledek.The enumeration of source is stopped as soon as the result can be determined.

V Visual Basic syntaxe výrazu dotazu je Aggregate Into Any() klauzule přeložena k vyvolání Any .In Visual Basic query expression syntax, an Aggregate Into Any() clause translates to an invocation of Any.

Viz také

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