BitArray.Get(Int32) 方法

定義

命名空間:

System.Collections

組件:

System.Collections.dll

來源:

BitArray.cs

取得 BitArray 中指定位置的位元值。

public:
 bool Get(int index);

public bool Get (int index);

member this.Get : int -> bool

Public Function Get (index As Integer) As Boolean

參數

index

Int32

要取得的值的以零為起始的索引。

傳回

Boolean

在 index 位置的位元值。

例外狀況

ArgumentOutOfRangeException

index 小於零。

-或-

index 大於或等於 BitArray 中的項目數。

範例

下列程式代碼範例示範如何在 中 BitArray設定和取得特定元素。

using namespace System;
using namespace System::Collections;
void PrintIndexAndValues( IEnumerable^ myCol );
int main()
{
   
   // Creates and initializes a BitArray.
   BitArray^ myBA = gcnew BitArray( 5 );
   
   // Displays the properties and values of the BitArray.
   Console::WriteLine( "myBA values:" );
   PrintIndexAndValues( myBA );
   
   // Sets all the elements to true.
   myBA->SetAll( true );
   
   // Displays the properties and values of the BitArray.
   Console::WriteLine( "After setting all elements to true," );
   PrintIndexAndValues( myBA );
   
   // Sets the last index to false.
   myBA->Set( myBA->Count - 1, false );
   
   // Displays the properties and values of the BitArray.
   Console::WriteLine( "After setting the last element to false," );
   PrintIndexAndValues( myBA );
   
   // Gets the value of the last two elements.
   Console::WriteLine( "The last two elements are: " );
   Console::WriteLine( "    at index {0} : {1}", myBA->Count - 2, myBA->Get( myBA->Count - 2 ) );
   Console::WriteLine( "    at index {0} : {1}", myBA->Count - 1, myBA->Get( myBA->Count - 1 ) );
}

void PrintIndexAndValues( IEnumerable^ myCol )
{
   int i = 0;
   IEnumerator^ myEnum = myCol->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::WriteLine( "    [{0}]:    {1}", i++, obj );
   }

   Console::WriteLine();
}

/* 
 This code produces the following output.
 
 myBA values:
     [0]:    False
     [1]:    False
     [2]:    False
     [3]:    False
     [4]:    False

 After setting all elements to true,
     [0]:    True
     [1]:    True
     [2]:    True
     [3]:    True
     [4]:    True

 After setting the last element to false,
     [0]:    True
     [1]:    True
     [2]:    True
     [3]:    True
     [4]:    False

 The last two elements are:
     at index 3 : True
     at index 4 : False

 */

using System;
using System.Collections;
public class SamplesBitArray  {

   public static void Main()  {

      // Creates and initializes a BitArray.
      BitArray myBA = new BitArray( 5 );

      // Displays the properties and values of the BitArray.
      Console.WriteLine( "myBA values:" );
      PrintIndexAndValues( myBA );

      // Sets all the elements to true.
      myBA.SetAll( true );

      // Displays the properties and values of the BitArray.
      Console.WriteLine( "After setting all elements to true," );
      PrintIndexAndValues( myBA );

      // Sets the last index to false.
      myBA.Set( myBA.Count - 1, false );

      // Displays the properties and values of the BitArray.
      Console.WriteLine( "After setting the last element to false," );
      PrintIndexAndValues( myBA );

      // Gets the value of the last two elements.
      Console.WriteLine( "The last two elements are: " );
      Console.WriteLine( "    at index {0} : {1}", myBA.Count - 2, myBA.Get( myBA.Count - 2 ) );
      Console.WriteLine( "    at index {0} : {1}", myBA.Count - 1, myBA.Get( myBA.Count - 1 ) );
   }

   public static void PrintIndexAndValues( IEnumerable myCol )  {
      int i = 0;
      foreach ( Object obj in myCol ) {
         Console.WriteLine( "    [{0}]:    {1}", i++, obj );
      }
      Console.WriteLine();
   }
}
/*
This code produces the following output.

myBA values:
    [0]:    False
    [1]:    False
    [2]:    False
    [3]:    False
    [4]:    False

After setting all elements to true,
    [0]:    True
    [1]:    True
    [2]:    True
    [3]:    True
    [4]:    True

After setting the last element to false,
    [0]:    True
    [1]:    True
    [2]:    True
    [3]:    True
    [4]:    False

The last two elements are:
    at index 3 : True
    at index 4 : False

*/

Imports System.Collections

Public Class SamplesBitArray    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a BitArray.
        Dim myBA As New BitArray(5)
        
        ' Displays the properties and values of the BitArray.
        Console.WriteLine("myBA values:")
        PrintIndexAndValues(myBA)
        
        ' Sets all the elements to true.
        myBA.SetAll(True)
        
        ' Displays the properties and values of the BitArray.
        Console.WriteLine("After setting all elements to true,")
        PrintIndexAndValues(myBA)
        
        ' Sets the last index to false.
        myBA.Set(myBA.Count - 1, False)
        
        ' Displays the properties and values of the BitArray.
        Console.WriteLine("After setting the last element to false,")
        PrintIndexAndValues(myBA)
        
        ' Gets the value of the last two elements.
        Console.WriteLine("The last two elements are: ")
        Console.WriteLine("    at index {0} : {1}", _
           myBA.Count - 2, myBA.Get(myBA.Count - 2))
        Console.WriteLine("    at index {0} : {1}", _
           myBA.Count - 1, myBA.Get(myBA.Count - 1))
    End Sub

    Public Shared Sub PrintIndexAndValues(myCol As IEnumerable)
        Dim i As Integer
        Dim obj As Object
        i = 0
        For Each obj In  myCol
            Console.WriteLine("    [{0}]:    {1}", i, obj)
            i = i + 1
        Next obj
        Console.WriteLine()
    End Sub

End Class

' This code produces the following output.
' 
' myBA values:
'     [0]:    False
'     [1]:    False
'     [2]:    False
'     [3]:    False
'     [4]:    False
' 
' After setting all elements to true,
'     [0]:    True
'     [1]:    True
'     [2]:    True
'     [3]:    True
'     [4]:    True
' 
' After setting the last element to false,
'     [0]:    True
'     [1]:    True
'     [2]:    True
'     [3]:    True
'     [4]:    False
' 
' The last two elements are:
'     at index 3 : True
'     at index 4 : False

備註

這個方法是 O(1) 作業。