Array.FindAll(T[], Predicate<T>) Array.FindAll(T[], Predicate<T>) Array.FindAll(T[], Predicate<T>) Array.FindAll(T[], Predicate<T>) Method

定義

指定された述語によって定義された条件と一致するすべての要素を取得します。 Retrieves all the elements that match the conditions defined by the specified predicate.

public:
generic <typename T>
 static cli::array <T> ^ FindAll(cli::array <T> ^ array, Predicate<T> ^ match);
public static T[] FindAll<T> (T[] array, Predicate<T> match);
static member FindAll : 'T[] * Predicate<'T> -> 'T[]
Public Shared Function FindAll(Of T) (array As T(), match As Predicate(Of T)) As T()
型パラメーター
T

配列要素の型。 The type of the elements of the array.

パラメーター
array
T[]

検索する 1 次元の Array。インデックス番号は 0 から始まります。 The one-dimensional, zero-based Array to search.

match
Predicate<T> Predicate<T> Predicate<T> Predicate<T>

検索する要素の条件を定義する Predicate<T> The Predicate<T> that defines the conditions of the elements to search for.

戻り値
T[]

見つかった場合は、指定された述語によって定義された条件と一致するすべての要素を格納した Array。それ以外の場合は、空の Array An Array containing all the elements that match the conditions defined by the specified predicate, if found; otherwise, an empty Array.

例外

arraynullです。 array is null. - または - -or- matchnullです。 match is null.

次の例では、0 から 1000 の範囲は値を持つ 50 の乱数の配列を作成します。The following example creates an array of 50 random numbers with values that can range from 0 to 1,000. 呼び出して、FindAllを 600 に 300 から値の範囲を返すラムダ式を持つメソッド。It then calls the FindAll method with a lambda expression that returns the values that range from 300 to 600. ラムダ式のという名前のパラメーターが渡されることに注意してくださいx;。 これに渡される個々 の配列のメンバーを表します、Predicate<T>します。Note that the lambda expression is passed a parameter named x; this represents the individual array member that is passed to the Predicate<T>. また、ローカルlBounduBound変数は、ラムダ式内でアクセスできます。Also note that the local lBound and uBound variables are accessible within the lambda expression.

using System;
using System.Collections.Generic;

public class Example
{
   public static void Main()
   {
      // Get an array of n random integers.
      int[] values = GetArray(50, 0, 1000);
      int lBound = 300;
      int uBound = 600;
      int[] matchedItems = Array.FindAll(values, x =>  
                                       x >= lBound && x <= uBound);  
      for (int ctr = 0; ctr < matchedItems.Length; ctr++) {
         Console.Write("{0}  ", matchedItems[ctr]);
         if ((ctr + 1) % 12 == 0)
            Console.WriteLine();
      }
   }

   private static int[] GetArray(int n, int lower, int upper)
   {
      Random rnd = new Random();
      List<int> list = new List<int>();
      for (int ctr = 1; ctr <= n; ctr++)
         list.Add(rnd.Next(lower, upper + 1));

      return list.ToArray();
   }
}
// The example displays output similar to the following:
//       542  398  356  351  348  301  562  599  575  400  569  306
//       535  416  393  385
Imports System.Collections.Generic

Module Example
   Public Sub Main()
      ' Get an array of n random integers.
      Dim values() As Integer = GetArray(50, 0, 1000)
      Dim lBound As Integer = 300
      Dim uBound As Integer = 600
      Dim matchedItems() As Integer = Array.FindAll(values, 
                                            Function(x) x >= lBound And x <= uBound)  
      For ctr As Integer = 0 To matchedItems.Length - 1
         Console.Write("{0}  ", matchedItems(ctr))
         If (ctr + 1) Mod 12 = 0 Then Console.WriteLine()
      Next
   End Sub
   
   Private Function GetArray(n As Integer, lower As Integer, 
                             upper As Integer) As Integer()
      Dim rnd As New Random()
      Dim list As New List(Of Integer)
      For ctr As Integer = 1 To n
         list.Add(rnd.Next(lower, upper + 1))
      Next
      Return list.ToArray()
   End Function
End Module
' The example displays output similar to the following:
'       542  398  356  351  348  301  562  599  575  400  569  306
'       535  416  393  385

次のコード例に示します、 FindFindLast、およびFindAllジェネリック メソッド。The following code example demonstrates the Find, FindLast, and FindAll generic methods. "Saurus"で終わる (位置 1 と 5) での 2 つの 8 恐竜の名前を含む文字列の配列が作成されます。An array of strings is created, containing 8 dinosaur names, two of which (at positions 1 and 5) end with "saurus". コード例では、という名前の検索述語メソッドも定義しますEndsWithSaurus、文字列パラメーターを受け入れるし、ブール値を返しますが、入力文字列では"かどうかを示すを値します。The code example also defines a search predicate method named EndsWithSaurus, which accepts a string parameter and returns a Boolean value indicating whether the input string ends in "saurus".

Findジェネリック メソッドでは、配列を走査の各要素を順番に渡す、最初から、EndsWithSaurusメソッド。The Find generic method traverses the array from the beginning, passing each element in turn to the EndsWithSaurus method. 検索を停止するときに、EndsWithSaurusメソッドを返します。true要素"Amargasaurus"。The search stops when the EndsWithSaurus method returns true for the element "Amargasaurus".

注意

C# および Visual Basic の場合でない作成に必要なPredicate<string>デリゲート (Predicate(Of String) Visual Basic で) 明示的にします。In C# and Visual Basic, it is not necessary to create the Predicate<string> delegate (Predicate(Of String) in Visual Basic) explicitly. これらの言語では、コンテキストから適切なデリゲート推測し、自動的に作成します。These languages infer the correct delegate from context and create it automatically.

FindLast末尾から旧バージョンとの配列を検索するジェネリック メソッドを使用します。The FindLast generic method is used to search the array backward from the end. 5 番目の位置にある"Dilophosaurus"要素を検索します。It finds the element "Dilophosaurus" at position 5. FindAllで終わるすべての要素を含む配列を返すジェネリック メソッドを使用します。The FindAll generic method is used to return an array containing all the elements that end in "saurus". 要素が表示されます。The elements are displayed.

コード例も示しています、ExistsTrueForAllジェネリック メソッド。The code example also demonstrates the Exists and TrueForAll generic methods.

using namespace System;

public ref class DinoDiscoverySet
{
public:
    static void Main()
    {
        array<String^>^ dinosaurs =
        {
            "Compsognathus", "Amargasaurus", "Oviraptor",
            "Velociraptor",  "Deinonychus",  "Dilophosaurus",
            "Gallimimus",    "Triceratops"
        };

        DinoDiscoverySet^ GoMesozoic = gcnew DinoDiscoverySet(dinosaurs);

        GoMesozoic->DiscoverAll();
        GoMesozoic->DiscoverByEnding("saurus");
    }

    DinoDiscoverySet(array<String^>^ items)
    {
        dinosaurs = items;
    }

    void DiscoverAll()
    {
        Console::WriteLine();
        for each(String^ dinosaur in dinosaurs)
        {
            Console::WriteLine(dinosaur);
        }
    }

    void DiscoverByEnding(String^ Ending)
    {
        Predicate<String^>^ dinoType;

        if (Ending->ToLower() == "raptor")
        {
            dinoType =
                gcnew Predicate<String^>(&DinoDiscoverySet::EndsWithRaptor);
        }
        else if (Ending->ToLower() == "tops")
        {
            dinoType =
                gcnew Predicate<String^>(&DinoDiscoverySet::EndsWithTops);
        }
        else if (Ending->ToLower() == "saurus")
        {
            dinoType =
                gcnew Predicate<String^>(&DinoDiscoverySet::EndsWithSaurus);
        }
        else
        {
            dinoType =
                gcnew Predicate<String^>(&DinoDiscoverySet::EndsWithSaurus);
        }

        Console::WriteLine(
            "\nArray::Exists(dinosaurs, \"{0}\"): {1}",
            Ending,
            Array::Exists(dinosaurs, dinoType));

        Console::WriteLine(
            "\nArray::TrueForAll(dinosaurs, \"{0}\"): {1}",
            Ending,
            Array::TrueForAll(dinosaurs, dinoType));

        Console::WriteLine(
            "\nArray::Find(dinosaurs, \"{0}\"): {1}",
            Ending,
            Array::Find(dinosaurs, dinoType));

        Console::WriteLine(
            "\nArray::FindLast(dinosaurs, \"{0}\"): {1}",
            Ending,
            Array::FindLast(dinosaurs, dinoType));

        Console::WriteLine(
            "\nArray::FindAll(dinosaurs, \"{0}\"):", Ending);

        array<String^>^ subArray =
            Array::FindAll(dinosaurs, dinoType);

        for each(String^ dinosaur in subArray)
        {
            Console::WriteLine(dinosaur);
        }
    }

private:
    array<String^>^ dinosaurs;

    // Search predicate returns true if a string ends in "saurus".
    static bool EndsWithSaurus(String^ s)
    {
        if ((s->Length > 5) &&
            (s->Substring(s->Length - 6)->ToLower() == "saurus"))
        {
            return true;
        }
        else
        {
            return false;
        }
    }

    // Search predicate returns true if a string ends in "raptor".
    static bool EndsWithRaptor(String^ s)
    {
        if ((s->Length > 5) &&
            (s->Substring(s->Length - 6)->ToLower() == "raptor"))
        {
            return true;
        }
        else
        {
            return false;
        }
    }

    // Search predicate returns true if a string ends in "tops".
    static bool EndsWithTops(String^ s)
    {
        if ((s->Length > 3) &&
            (s->Substring(s->Length - 4)->ToLower() == "tops"))
        {
            return true;
        }
        else
        {
            return false;
        }
    }
};

int main()
{
    DinoDiscoverySet::Main();
}

/* This code example produces the following output:

Compsognathus
Amargasaurus
Oviraptor
Velociraptor
Deinonychus
Dilophosaurus
Gallimimus
Triceratops

Array.Exists(dinosaurs, "saurus"): True

Array.TrueForAll(dinosaurs, "saurus"): False

Array.Find(dinosaurs, "saurus"): Amargasaurus

Array.FindLast(dinosaurs, "saurus"): Dilophosaurus

Array.FindAll(dinosaurs, "saurus"):
Amargasaurus
Dilophosaurus
*/
using System;

public class DinoDiscoverySet
{
    public static void Main()
    {
        string[] dinosaurs =
        {
            "Compsognathus", "Amargasaurus", "Oviraptor",
            "Velociraptor",  "Deinonychus",  "Dilophosaurus",
            "Gallimimus",    "Triceratops"
        };

        DinoDiscoverySet GoMesozoic = new DinoDiscoverySet(dinosaurs);
        
        GoMesozoic.DiscoverAll();
        GoMesozoic.DiscoverByEnding("saurus");
    }

    private string[] dinosaurs;

    public DinoDiscoverySet(string[] items)
    {
        dinosaurs = items;
    }

    public void DiscoverAll()
    {
        Console.WriteLine();
        foreach(string dinosaur in dinosaurs)
        {
            Console.WriteLine(dinosaur);
        }
    }

    public void DiscoverByEnding(string Ending)
    {
        Predicate<string> dinoType;

        switch (Ending.ToLower())
        {
            case "raptor":
                dinoType = EndsWithRaptor;
                break;
            case "tops":
                dinoType = EndsWithTops;
                break;
            case "saurus":
            default:
                dinoType = EndsWithSaurus;
                break;
        }
        Console.WriteLine(
            "\nArray.Exists(dinosaurs, \"{0}\"): {1}",
            Ending,
            Array.Exists(dinosaurs, dinoType));

        Console.WriteLine(
            "\nArray.TrueForAll(dinosaurs, \"{0}\"): {1}",
            Ending,
            Array.TrueForAll(dinosaurs, dinoType));

        Console.WriteLine(
            "\nArray.Find(dinosaurs, \"{0}\"): {1}",
            Ending,
            Array.Find(dinosaurs, dinoType));

        Console.WriteLine(
            "\nArray.FindLast(dinosaurs, \"{0}\"): {1}",
            Ending,
            Array.FindLast(dinosaurs, dinoType));

        Console.WriteLine(
            "\nArray.FindAll(dinosaurs, \"{0}\"):", Ending);

        string[] subArray =
            Array.FindAll(dinosaurs, dinoType);

        foreach(string dinosaur in subArray)
        {
            Console.WriteLine(dinosaur);
        }
    }

    // Search predicate returns true if a string ends in "saurus".
    private bool EndsWithSaurus(string s)
    {
        if ((s.Length > 5) &&
            (s.Substring(s.Length - 6).ToLower() == "saurus"))
        {
            return true;
        }
        else
        {
            return false;
        }
    }

    // Search predicate returns true if a string ends in "raptor".
    private bool EndsWithRaptor(String s)
    {
        if ((s.Length > 5) &&
            (s.Substring(s.Length - 6).ToLower() == "raptor"))
        {
            return true;
        }
        else
        {
            return false;
        }
    }

    // Search predicate returns true if a string ends in "tops".
    private bool EndsWithTops(String s)
    {
        if ((s.Length > 3) &&
            (s.Substring(s.Length - 4).ToLower() == "tops"))
        {
            return true;
        }
        else
        {
            return false;
        }
    }
}

/* This code example produces the following output:

Compsognathus
Amargasaurus
Oviraptor
Velociraptor
Deinonychus
Dilophosaurus
Gallimimus
Triceratops

Array.Exists(dinosaurs, "saurus"): True

Array.TrueForAll(dinosaurs, "saurus"): False

Array.Find(dinosaurs, "saurus"): Amargasaurus

Array.FindLast(dinosaurs, "saurus"): Dilophosaurus

Array.FindAll(dinosaurs, "saurus"):
Amargasaurus
Dilophosaurus
*/
Imports System

Public Class DinoDiscoverySet

    Public Shared Sub Main()
        Dim dinosaurs() As String = { "Compsognathus", _
            "Amargasaurus",   "Oviraptor",      "Velociraptor", _
            "Deinonychus",    "Dilophosaurus",  "Gallimimus", _
            "Triceratops" }

        Dim GoMesozoic As New DinoDiscoverySet(dinosaurs)

        GoMesozoic.DiscoverAll()
        GoMesozoic.DiscoverByEnding("saurus")
    End Sub

    Private dinosaurs As String()

    Public Sub New(items() As String)
        dinosaurs = items
    End Sub

    Public Sub DiscoverAll()
        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next dinosaur
    End Sub

    Public Sub DiscoverByEnding(Ending As String)
        Dim dinoType As Predicate(Of String)

        Select Case Ending.ToLower()
            Case "raptor"
                dinoType = AddressOf EndsWithRaptor
            Case "tops"
                dinoType = AddressOf EndsWithTops
            Case "saurus"
                dinoType = AddressOf EndsWithSaurus
            Case Else
                dinoType = AddressOf EndsWithSaurus
        End Select

        Console.WriteLine(vbNewLine + _
            "Array.Exists(dinosaurs, ""{0}""): {1}", _
            Ending, _
            Array.Exists(dinosaurs, dinoType))

        Console.WriteLine(vbNewLine + _
            "Array.TrueForAll(dinosaurs, ""{0}""): {1}", _
            Ending, _
            Array.TrueForAll(dinosaurs, dinoType))

        Console.WriteLine(vbNewLine + _
            "Array.Find(dinosaurs, ""{0}""): {1}", _
            Ending, _
            Array.Find(dinosaurs, dinoType))

        Console.WriteLine(vbNewLine + _
            "Array.FindLast(dinosaurs, ""{0}""): {1}", _
            Ending, _
            Array.FindLast(dinosaurs, dinoType))

        Console.WriteLine(vbNewLine + _
            "Array.FindAll(dinosaurs, ""{0}""):", Ending)

        Dim subArray() As String = _
            Array.FindAll(dinosaurs, dinoType)

        For Each dinosaur As String In subArray
            Console.WriteLine(dinosaur)
        Next dinosaur
    End Sub

    ' Search predicate returns true if a string ends in "saurus".
    Private Function EndsWithSaurus(s As String) As Boolean
        ' AndAlso prevents evaluation of the second Boolean
        ' expression if the string is so short that an error
        ' would occur.
        If (s.Length > 5) AndAlso _
            (s.ToLower().EndsWith("saurus")) Then
            Return True
        Else
            Return False
        End If
    End Function

    ' Search predicate returns true if a string ends in "raptor".
    Private Function EndsWithRaptor(s As String) As Boolean
        ' AndAlso prevents evaluation of the second Boolean
        ' expression if the string is so short that an error
        ' would occur.
        If (s.Length > 5) AndAlso _
            (s.ToLower().EndsWith("raptor")) Then
            Return True
        Else
            Return False
        End If
    End Function

    ' Search predicate returns true if a string ends in "tops".
    Private Function EndsWithTops(s As String) As Boolean
        ' AndAlso prevents evaluation of the second Boolean
        ' expression if the string is so short that an error
        ' would occur.
        If (s.Length > 3) AndAlso _
            (s.ToLower().EndsWith("tops")) Then
            Return True
        Else
            Return False
        End If
    End Function
End Class

' This code example produces the following output:
'
' Compsognathus
' Amargasaurus
' Oviraptor
' Velociraptor
' Deinonychus
' Dilophosaurus
' Gallimimus
' Triceratops
'
' Array.Exists(dinosaurs, "saurus"): True
'
' Array.TrueForAll(dinosaurs, "saurus"): False
'
' Array.Find(dinosaurs, "saurus"): Amargasaurus
'
' Array.FindLast(dinosaurs, "saurus"): Dilophosaurus
'
' Array.FindAll(dinosaurs, "saurus"):
' Amargasaurus
' Dilophosaurus

注釈

Predicate<T>を返すメソッドにデリゲートtrueデリゲートで定義されている条件に一致するオブジェクトが渡された場合。The Predicate<T> is a delegate to a method that returns true if the object passed to it matches the conditions defined in the delegate. 要素arrayに個別に渡される、Predicate<T>条件に一致する要素が返される配列に保存されます。The elements of array are individually passed to the Predicate<T>, and the elements that match the conditions are saved in the returned array.

このメソッドは O (n) 操作、nは、Lengtharrayします。This method is an O(n) operation, where n is the Length of array.

適用対象

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