BitArray Class
Manages a compact array of bit values, which are represented as Booleans, where true indicates that the bit is on (1) and false indicates the bit is off (0).
For a list of all members of this type, see BitArray Members.
System.Object
System.Collections.BitArray
[Visual Basic] <Serializable> NotInheritable Public Class BitArray Implements ICollection, IEnumerable, ICloneable [C#] [Serializable] public sealed class BitArray : ICollection, IEnumerable, ICloneable [C++] [Serializable] public __gc __sealed class BitArray : public ICollection, IEnumerable, ICloneable [JScript] public Serializable class BitArray implements ICollection, IEnumerable, ICloneable
Thread Safety
Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.
This implementation does not provide a synchronized (thread-safe) wrapper for a BitArray.
Enumerating through a collection is intrinsically not a thread-safe procedure. Even when a collection is synchronized, other threads could still modify the collection, which causes the enumerator to throw an exception. To guarantee thread safety during enumeration, you can either lock the collection during the entire enumeration or catch the exceptions resulting from changes made by other threads.
Remarks
The size of a BitArray is controlled by the client; indexing past the end of the BitArray throws an ArgumentException.
Indexes in this collection are zero-based.
Example
[Visual Basic, C#, C++] The following example shows how to create and initialize a BitArray and how to print out its values.
[Visual Basic] Imports System Imports System.Collections Imports Microsoft.VisualBasic Public Class SamplesBitArray Public Shared Sub Main() ' Creates and initializes several BitArrays. Dim myBA1 As New BitArray(5) Dim myBA2 As New BitArray(5, False) Dim myBytes() As Byte = {1, 2, 3, 4, 5} Dim myBA3 As New BitArray(myBytes) Dim myBools() As Boolean = {True, False, True, True, False} Dim myBA4 As New BitArray(myBools) Dim myInts() As Integer = {6, 7, 8, 9, 10} Dim myBA5 As New BitArray(myInts) ' Displays the properties and values of the BitArrays. Console.WriteLine("myBA1") Console.WriteLine(ControlChars.Tab + "Count: {0}", myBA1.Count) Console.WriteLine(ControlChars.Tab + "Length: {0}", myBA1.Length) Console.WriteLine(ControlChars.Tab + "Values:") PrintValues(myBA1, 8) Console.WriteLine("myBA2") Console.WriteLine(ControlChars.Tab + "Count: {0}", myBA2.Count) Console.WriteLine(ControlChars.Tab + "Length: {0}", myBA2.Length) Console.WriteLine(ControlChars.Tab + "Values:") PrintValues(myBA2, 8) Console.WriteLine("myBA3") Console.WriteLine(ControlChars.Tab + "Count: {0}", myBA3.Count) Console.WriteLine(ControlChars.Tab + "Length: {0}", myBA3.Length) Console.WriteLine(ControlChars.Tab + "Values:") PrintValues(myBA3, 8) Console.WriteLine("myBA4") Console.WriteLine(ControlChars.Tab + "Count: {0}", myBA4.Count) Console.WriteLine(ControlChars.Tab + "Length: {0}", myBA4.Length) Console.WriteLine(ControlChars.Tab + "Values:") PrintValues(myBA4, 8) Console.WriteLine("myBA5") Console.WriteLine(ControlChars.Tab + "Count: {0}", myBA5.Count) Console.WriteLine(ControlChars.Tab + "Length: {0}", myBA5.Length) Console.WriteLine(ControlChars.Tab + "Values:") PrintValues(myBA5, 8) End Sub Public Shared Sub PrintValues(myList As IEnumerable, myWidth As Integer) Dim myEnumerator As System.Collections.IEnumerator = _ myList.GetEnumerator() Dim i As Integer = myWidth While myEnumerator.MoveNext() If i <= 0 Then i = myWidth Console.WriteLine() End If i -= 1 Console.Write(ControlChars.Tab + "{0}", myEnumerator.Current) End While Console.WriteLine() End Sub End Class ' This code produces the following output. ' ' myBA1 ' Count: 5 ' Length: 5 ' Values: ' False False False False False ' myBA2 ' Count: 5 ' Length: 5 ' Values: ' False False False False False ' myBA3 ' Count: 40 ' Length: 40 ' Values: ' True False False False False False False False ' False True False False False False False False ' True True False False False False False False ' False False True False False False False False ' True False True False False False False False ' myBA4 ' Count: 5 ' Length: 5 ' Values: ' True False True True False ' myBA5 ' Count: 160 ' Length: 160 ' Values: ' False True True False False False False False ' False False False False False False False False ' False False False False False False False False ' False False False False False False False False ' True True True False False False False False ' False False False False False False False False ' False False False False False False False False ' False False False False False False False False ' False False False True False False False False ' False False False False False False False False ' False False False False False False False False ' False False False False False False False False ' True False False True False False False False ' False False False False False False False False ' False False False False False False False False ' False False False False False False False False ' False True False True False False False False ' False False False False False False False False ' False False False False False False False False ' False False False False False False False False [C#] using System; using System.Collections; public class SamplesBitArray { public static void Main() { // Creates and initializes several BitArrays. BitArray myBA1 = new BitArray( 5 ); BitArray myBA2 = new BitArray( 5, false ); byte[] myBytes = new byte[5] { 1, 2, 3, 4, 5 }; BitArray myBA3 = new BitArray( myBytes ); bool[] myBools = new bool[5] { true, false, true, true, false }; BitArray myBA4 = new BitArray( myBools ); int[] myInts = new int[5] { 6, 7, 8, 9, 10 }; BitArray myBA5 = new BitArray( myInts ); // Displays the properties and values of the BitArrays. Console.WriteLine( "myBA1" ); Console.WriteLine( "\tCount: {0}", myBA1.Count ); Console.WriteLine( "\tLength: {0}", myBA1.Length ); Console.WriteLine( "\tValues:" ); PrintValues( myBA1, 8 ); Console.WriteLine( "myBA2" ); Console.WriteLine( "\tCount: {0}", myBA2.Count ); Console.WriteLine( "\tLength: {0}", myBA2.Length ); Console.WriteLine( "\tValues:" ); PrintValues( myBA2, 8 ); Console.WriteLine( "myBA3" ); Console.WriteLine( "\tCount: {0}", myBA3.Count ); Console.WriteLine( "\tLength: {0}", myBA3.Length ); Console.WriteLine( "\tValues:" ); PrintValues( myBA3, 8 ); Console.WriteLine( "myBA4" ); Console.WriteLine( "\tCount: {0}", myBA4.Count ); Console.WriteLine( "\tLength: {0}", myBA4.Length ); Console.WriteLine( "\tValues:" ); PrintValues( myBA4, 8 ); Console.WriteLine( "myBA5" ); Console.WriteLine( "\tCount: {0}", myBA5.Count ); Console.WriteLine( "\tLength: {0}", myBA5.Length ); Console.WriteLine( "\tValues:" ); PrintValues( myBA5, 8 ); } public static void PrintValues( IEnumerable myList, int myWidth ) { System.Collections.IEnumerator myEnumerator = myList.GetEnumerator(); int i = myWidth; while ( myEnumerator.MoveNext() ) { if ( i <= 0 ) { i = myWidth; Console.WriteLine(); } i--; Console.Write( "\t{0}", myEnumerator.Current ); } Console.WriteLine(); } } /* This code produces the following output. myBA1 Count: 5 Length: 5 Values: False False False False False myBA2 Count: 5 Length: 5 Values: False False False False False myBA3 Count: 40 Length: 40 Values: True False False False False False False False False True False False False False False False True True False False False False False False False False True False False False False False True False True False False False False False myBA4 Count: 5 Length: 5 Values: True False True True False myBA5 Count: 160 Length: 160 Values: False True True False False False False False False False False False False False False False False False False False False False False False False False False False False False False False True True True False False False False False False False False False False False False False False False False False False False False False False False False False False False False False False False False True False False False False False False False False False False False False False False False False False False False False False False False False False False False False True False False True False False False False False False False False False False False False False False False False False False False False False False False False False False False False False True False True False False False False False False False False False False False False False False False False False False False False False False False False False False False False */ [C++] #using <mscorlib.dll> #using <system.dll> using namespace System; using namespace System::Collections; void PrintValues( IEnumerable* myList, int myWidth ) { System::Collections::IEnumerator* myEnumerator = myList->GetEnumerator(); int i = myWidth; while ( myEnumerator->MoveNext() ) { if ( i <= 0 ) { i = myWidth; Console::WriteLine(); } i--; Console::Write( S"\t{0}", myEnumerator->Current ); } Console::WriteLine(); } int main() { // Creates and initializes several BitArrays. BitArray* myBA1 = new BitArray( 5 ); BitArray* myBA2 = new BitArray( 5, false ); Byte myBytes[] = new Byte[5]; for( int i(0); i < myBytes->Length; ++i ) { myBytes[i] = i+1; } BitArray* myBA3 = new BitArray( myBytes ); bool myBools __gc[] = new bool __gc[5]; for( int i(0); i < myBools->Length; ++i ) { myBools[i] = (i % 2 == 0); } BitArray* myBA4 = new BitArray( myBools ); int myInts __gc[] = new int __gc[5]; for( int i(0); i < myInts->Length; ++i ) { myInts[i] = i+6; } BitArray* myBA5 = new BitArray( myInts ); // Displays the properties and values of the BitArrays. Console::WriteLine( S"myBA1" ); Console::WriteLine( S"\tCount: {0}", __box(myBA1->Count) ); Console::WriteLine( S"\tLength: {0}", __box(myBA1->Length) ); Console::WriteLine( S"\tValues:" ); PrintValues( myBA1, 8 ); Console::WriteLine( S"myBA2" ); Console::WriteLine( S"\tCount: {0}", __box(myBA2->Count) ); Console::WriteLine( S"\tLength: {0}", __box(myBA2->Length) ); Console::WriteLine( S"\tValues:" ); PrintValues( myBA2, 8 ); Console::WriteLine( S"myBA3" ); Console::WriteLine( S"\tCount: {0}", __box(myBA3->Count) ); Console::WriteLine( S"\tLength: {0}", __box(myBA3->Length) ); Console::WriteLine( S"\tValues:" ); PrintValues( myBA3, 8 ); Console::WriteLine( S"myBA4" ); Console::WriteLine( S"\tCount: {0}", __box(myBA4->Count) ); Console::WriteLine( S"\tLength: {0}", __box(myBA4->Length) ); Console::WriteLine( S"\tValues:" ); PrintValues( myBA4, 8 ); Console::WriteLine( S"myBA5" ); Console::WriteLine( S"\tCount: {0}", __box(myBA5->Count) ); Console::WriteLine( S"\tLength: {0}", __box(myBA5->Length) ); Console::WriteLine( S"\tValues:" ); PrintValues( myBA5, 8 ); } /* This code produces the following output. myBA1 Count: 5 Length: 5 Values: False False False False False myBA2 Count: 5 Length: 5 Values: False False False False False myBA3 Count: 40 Length: 40 Values: True False False False False False False False False True False False False False False False True True False False False False False False False False True False False False False False True False True False False False False False myBA4 Count: 5 Length: 5 Values: True False True False True myBA5 Count: 160 Length: 160 Values: False True True False False False False False False False False False False False False False False False False False False False False False False False False False False False False False True True True False False False False False False False False False False False False False False False False False False False False False False False False False False False False False False False False True False False False False False False False False False False False False False False False False False False False False False False False False False False False False True False False True False False False False False False False False False False False False False False False False False False False False False False False False False False False False False True False True False False False False False False False False False False False False False False False False False False False False False False False False False False False False */
[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button
in the upper-left corner of the page.
Requirements
Namespace: System.Collections
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework
Assembly: Mscorlib (in Mscorlib.dll)