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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 383

`type TBits = class(TObject) end;`
`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.

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.