CBitArray

Description

Constructors

CBitArray()
CBitArray( DWORD initial_size )
CBitArray( const CBitArray& source )
CBitArray( const CByteArray& source )

Constructs this object.

Methods

void Add( DWORD bit_to_add, DWORD count = 1 )

Appends a new bit to the array. If bit_to_add is not zero, a 1-bit is added.

void AddByte( BYTE byte_to_add )

Appends byte (8 bits) to the array.

void AddValue( DWORD value_to_add, DWORD number_of_bits_in_value )

Appends a a value to the array. You specify how many bits are in value_to_add (up to 32).

void Append( const CBitArray& source  )
void Append( const BYTE * data, DWORD number_of_bytes )

Appends a whole bunch of bits to the array.

void Complement( void )

Turns every zero into a one and every one into a zero in the array.

void Copy( const CBitArray& source )
void Copy( const CByteArray& source )

Copies bits from the specified source.

void CopyTo( CByteArray& destination )
void CopyTo( CDWordArray& destination )

Exports the bits to the destination supplied.

BOOL Find( const CBitArray& value, DWORD& found_at, DWORD starting_at = 0 ) const
BOOL Find( DWORD value, DWORD number_of_bits_in_value, DWORD& found_at, DWORD starting_at = 0 ) const

Searches for a bit pattern in the array. If it returns TRUE, found_at will be filled with the index where the pattern begins.

void FreeExtra( void )

Compresses the memory used to store the bits.

DWORD GetAt( DWORD index ) const

Returns a 1 if the bit at that index is not zero. It will return 0 if that bit is a zero. If index is something wacky (i.e. passed the end of the array), it will return 0.

DWORD GetNumberOfOnes( void ) const

Returns the number of bits that are 1.

DWORD GetNumberOfZeroes( void ) const

Returns the number of bits that are 0.

DWORD GetSize( void ) const

Returns the number of bits in the array.

DWORD GetUpperBound( void ) const

Returns the current upper bound of this array. Because array indexes are zero-based, this function returns a value 1 less than GetSize().

DWORD GetValue( DWORD index, DWORD length ) const

Returns the value at the given location.

void InsertAt( DWORD index, DWORD value )

Inserts a single bit at the given index.

CBitArray Left( DWORD number_of_bits ) const

Returns the left-most number_of_bits.

void LeftTrim( DWORD number_of_bits )

Trims the number_of_bits from the beginning of the array.

CBitArray Mid( DWORD starting_at_index, DWORD number_of_bits ) const

Returns number_of_bits beginning at starting_at_index.

void RemoveAll( void )

Clears the array. It removes all bits.

void RemoveAt( DWORD index )

Removes a single bit at the given index.

CBitArray Right( DWORD number_of_bits )

Returns the last number_of_bits in the array.

void RightTrim( DWORD number_of_bits )

Removes the last number_of_bits from the array.

void Serialize( CArchive& archive )

After all, we are a CObject...

void SetAll( DWORD value )

Sets all of the bits in the array to value.

void SetAt( DWORD index, DWORD value )

Sets the bits at the given index to value.

void SetSize( DWORD size )

Allocates enough memory to hold size bits.

void SetValue( DWORD index, DWORD value, DWORD length )

Beginning at index, the bits in value will replace the bits in the array for length number of bits.

Operators

CBitArray& operator = ( const CBitArray& source )
CBitArray& operator = ( const CByteArray& source )

Basically calls Copy().

CBitArray& operator += ( const CBitArray& source )
CBitArray& operator += ( const CByteArray& source )

Basically calls Append().

DWORD operator [] ( int index ) const

Calls GetAt().

Example

#include <wfc.h>

int _tmain( int number_of_command_line_arguments, LPCTSTR command_line_arguments[] )
{
   WFCTRACEINIT( TEXT( "_tmain()" ) );

   CBitArray bits;

   bits.Add( 0x55 );

   _tprintf( TEXT( "Bit number 7 is %d\n", (int) bits.GetAt( 7 ) );

   bits.SetAt( 7, 0 ); // Turn bit 7 off
}