[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] | Reference for unit 'Classes' (#rtl)

# TBits

[Properties (by Name)] [Methods (by Name)] [Events (by Name)]

Class to store collections of bits (binary values that can be 0 or 1)

## Declaration

Source position: classesh.inc line 385

`type TBits = class(TObject)`
`public`
`constructor Create(); virtual;` |  | Creates a new bits collection.
`destructor Destroy; override;` |  | Destroys a bit collection
`function GetFSize;` |  | Returns the number of records used to store the bits.
`procedure SetOn();` |  | Turn a particular bit on.
`procedure Clear();` |  | Clears a particular bit.
`procedure Clearall;` |  | Clears all bits in the array.
`procedure AndBits();` |  | Performs an and operation on the bits.
`procedure OrBits();` |  | Performs an or operation on the bits.
`procedure XorBits();` |  | Performs a xor operation on the bits.
`procedure NotBits();` |  | Performs a not operation on the bits.
`function Get();` |  | Retrieve the value of a particular bit
`procedure Grow();` |  | Expands the bits array to the requested size.
`function Equals();` |  | Determines whether the bits of 2 arrays are equal.
`procedure SetIndex();` |  | Sets the start position for FindNextBit and FindPrevBit
`function FindFirstBit();` |  | Find first bit with a particular value
`function FindNextBit;` |  | Searches the next bit with a particular value.
`function FindPrevBit;` |  | Searches the previous bit with a particular value.
`function OpenBit;` |  | Returns the position of the first bit that is set to False.
`property Bits: Boolean; default; [rw]` |  | Access to all bits in the array.
`property Size: LongInt; [rw]` |  | Current size of the array of bits.
`end;`

## Inheritance

`TBits` |  | Class to store collections of bits (binary values that can be 0 or 1)
`TObject` |  | Base class of all classes.

## Description

TBits can be used to store collections of bits in an indexed array. This is especially useful for storing collections of booleans: Normally the size of a boolean is the size of the smallest enumerated type, i.e. 1 byte. Since a bit can take 2 values it can be used to store a boolean as well. Since TBits can store 8 bits in a byte, it takes 8 times less space to store an array of booleans in a TBits class then it would take to store them in a conventional array.

TBits introduces methods to store and retrieve bit values, apply masks, and search for bits.

Documentation generated on: Feb 26 2014