バイナリ サーチ アルゴリズムを使用して、並べ替え済みの 1 次元の Array 内で値を検索します。
オーバーロードの一覧
1 次元の並べ替え済み Array の各要素および指定したオブジェクトによって実装されている IComparable インターフェイスを使用して、その Array 全体の中から特定の要素を検索します。
.NET Compact Framework でもサポート。
[Visual Basic] Overloads Public Shared Function BinarySearch(Array, Object) As Integer
[JScript] public static function BinarySearch(Array, Object) : int;
指定した IComparer インターフェイスを使用して、1 次元の並べ替え済み Array 全体の中から値を検索します。
[Visual Basic] Overloads Public Shared Function BinarySearch(Array, Object, IComparer) As Integer
[C#] public static int BinarySearch(Array, object, IComparer);
[C++] public: static int BinarySearch(Array*, Object*, IComparer*);
[JScript] public static function BinarySearch(Array, Object, IComparer) : int;
1 次元の並べ替え済み Array の各要素および指定した値によって実装されている IComparable インターフェイスを使用して、その Array 範囲の中から値を検索します。
[Visual Basic] Overloads Public Shared Function BinarySearch(Array, Integer, Integer, Object) As Integer
[C#] public static int BinarySearch(Array, int, int, object);
[C++] public: static int BinarySearch(Array*, int, int, Object*);
[JScript] public static function BinarySearch(Array, int, int, Object) : int;
指定した IComparer インターフェイスを使用して、1 次元の並べ替え済み Array 範囲の中から値を検索します。
.NET Compact Framework でもサポート。
[Visual Basic] Overloads Public Shared Function BinarySearch(Array, Integer, Integer, Object, IComparer) As Integer
[C#] public static int BinarySearch(Array, int, int, object, IComparer);
[C++] public: static int BinarySearch(Array*, int, int, Object*, IComparer*);
[JScript] public static function BinarySearch(Array, int, int, Object, IComparer) : int;
使用例
BinarySearch を使用して Array 内の特定のオブジェクトを検索する方法を次のコード例に示します。
Imports System
Imports Microsoft.VisualBasic
Public Class SamplesArray
Public Shared Sub Main()
' Creates and initializes a new Array.
Dim myIntArray As Array = Array.CreateInstance(GetType(Int32), 5)
Dim i As Integer
For i = myIntArray.GetLowerBound(0) To myIntArray.GetUpperBound(0)
myIntArray.SetValue(i * 2, i)
Next i
' Displays the values of the Array.
Console.WriteLine("The Int32 array contains the following:")
PrintValues(myIntArray)
' Locates a specific object that does not exist in the Array.
Dim myObjectOdd As Object = 3
FindMyObject(myIntArray, myObjectOdd)
' Locates an object that exists in the Array.
Dim myObjectEven As Object = 6
FindMyObject(myIntArray, myObjectEven)
End Sub
Public Shared Sub FindMyObject(myArr As Array, myObject As Object)
Dim myIndex As Integer = Array.BinarySearch(myArr, myObject)
If myIndex < 0 Then
Console.WriteLine("The object to search for ({0}) is not found. " _
+ "The next larger object is at index {1}.", myObject, Not(myIndex))
Else
Console.WriteLine("The object to search for ({0}) is at index " _
+ "{1}.", myObject, myIndex)
End If
End Sub
Public Shared Sub PrintValues(myArr As Array)
Dim myEnumerator As System.Collections.IEnumerator = _
myArr.GetEnumerator()
Dim i As Integer = 0
Dim cols As Integer = myArr.GetLength((myArr.Rank - 1))
While myEnumerator.MoveNext()
If i < cols Then
i += 1
Else
Console.WriteLine()
i = 1
End If
Console.Write(ControlChars.Tab + "{0}", myEnumerator.Current)
End While
Console.WriteLine()
End Sub
End Class
' This code produces the following output.
'
' The Int32 array contains the following:
' 0 2 4 6 8
' The object to search for (3) is not found. The next larger object is at index 2.
' The object to search for (6) is at index 3.
[C#]
using System;
public class SamplesArray {
public static void Main() {
// Creates and initializes a new Array.
Array myIntArray = Array.CreateInstance( typeof(Int32), 5 );
for ( int i = myIntArray.GetLowerBound(0); i <= myIntArray.GetUpperBound(0); i++ )
myIntArray.SetValue( i*2, i );
// Displays the values of the Array.
Console.WriteLine( "The Int32 array contains the following:" );
PrintValues( myIntArray );
// Locates a specific object that does not exist in the Array.
Object myObjectOdd = 3;
FindMyObject( myIntArray, myObjectOdd );
// Locates an object that exists in the Array.
Object myObjectEven = 6;
FindMyObject( myIntArray, myObjectEven );
}
public static void FindMyObject( Array myArr, Object myObject ) {
int myIndex=Array.BinarySearch( myArr, myObject );
if ( myIndex < 0 )
Console.WriteLine( "The object to search for ({0}) is not found. The next larger object is at index {1}.", myObject, ~myIndex );
else
Console.WriteLine( "The object to search for ({0}) is at index {1}.", myObject, myIndex );
}
public static void PrintValues( Array myArr ) {
System.Collections.IEnumerator myEnumerator = myArr.GetEnumerator();
int i = 0;
int cols = myArr.GetLength( myArr.Rank - 1 );
while ( myEnumerator.MoveNext() ) {
if ( i < cols ) {
i++;
} else {
Console.WriteLine();
i = 1;
}
Console.Write( "\t{0}", myEnumerator.Current );
}
Console.WriteLine();
}
}
/*
This code produces the following output.
The Int32 array contains the following:
0 2 4 6 8
The object to search for (3) is not found. The next larger object is at index 2.
The object to search for (6) is at index 3.
*/
[C++]
#using <mscorlib.dll>
using namespace System;
void FindMyObject( Array* myArr, Object* myObject );
void PrintValues( Array* myArr );
void main() {
// Creates and initializes a new Array instance.
Array* myIntArray = Array::CreateInstance( __typeof(Int32), 5 );
for ( int i = myIntArray->GetLowerBound(0); i <= myIntArray->GetUpperBound(0); i++ )
myIntArray->SetValue( __box(i*2), i );
// Displays the values of the Array.
Console::WriteLine( "The Int32 array contains the following:" );
PrintValues( myIntArray );
// Locates a specific object that does not exist in the Array.
Object* myObjectOdd = __box(3);
FindMyObject( myIntArray, myObjectOdd );
// Locates an object that exists in the Array.
Object* myObjectEven = __box(6);
FindMyObject( myIntArray, myObjectEven );
}
void FindMyObject( Array* myArr, Object* myObject ) {
int myIndex = Array::BinarySearch( myArr, myObject );
if ( myIndex < 0 )
Console::WriteLine( "The object to search for ({0}) is not found. The next larger object is at index {1}.", myObject, __box(~myIndex) );
else
Console::WriteLine( "The object to search for ({0}) is at index {1}.", myObject, __box(myIndex) );
}
void PrintValues( Array* myArr ) {
System::Collections::IEnumerator* myEnumerator = myArr->GetEnumerator();
int i = 0;
int cols = myArr->GetLength( myArr->Rank - 1 );
while ( myEnumerator->MoveNext() ) {
if ( i < cols ) {
i++;
}
else {
Console::WriteLine();
i = 1;
}
Console::Write( "\t{0}", myEnumerator->Current );
}
Console::WriteLine();
}
/*
This code produces the following output.
The Int32 array contains the following:
0 2 4 6 8
The object to search for (3) is not found. The next larger object is at index 2.
The object to search for (6) is at index 3.
*/
[JScript]
import System
import System.Collections
// Creates and initializes a new Array.
var myIntArray : System.Array = System.Array.CreateInstance( Int32, 5);
for ( var i : int = myIntArray.GetLowerBound(0); i <= myIntArray.GetUpperBound(0); i++ )
myIntArray.SetValue( Int32(i*2), i );
// Displays the values of the Array.
Console.WriteLine( "The Int32 array contains the following:" );
PrintValues( myIntArray );
// Locates a specific object that does not exist in the Array.
var myObjectOdd : Object = 3;
FindMyObject( myIntArray, myObjectOdd );
// Locates an object that exists in the Array.
var myObjectEven : Object = 6;
FindMyObject( myIntArray, myObjectEven );
function FindMyObject( myArr : System.Array, myObject : Object) {
var myIndex : int = System.Array.BinarySearch( myArr, myObject );
if ( myIndex < 0 )
Console.WriteLine( "The object to search for ({0}) is not found. " +
"The next larger object is at index {1}.", myObject, ~myIndex );
else
Console.WriteLine( "The object to search for ({0}) is at index {1}.", myObject, myIndex );
}
function PrintValues( myArr : System.Array ) {
var arrEnum : IEnumerator = myArr.GetEnumerator();
arrEnum.Reset();
while (arrEnum.MoveNext()) {
Console.Write( "{0,-6}", arrEnum.Current.ToString());
}
Console.WriteLine();
}
/*
This code produces the following output.
The Int32 array contains the following:
0 2 4 6 8
The object to search for (3) is not found. The next larger object is at index 2.
The object to search for (6) is at index 3.
*/