C# Class Adler32.AdlerChecksum

Adler 32 check sum calculation (From en.wikipedia.org) Adler-32 is a checksum algorithm which was invented by Mark Adler. It is almost as reliable as a 32-bit cyclic redundancy check for protecting against accidental modification of data, such as distortions occurring during a transmission. An Adler-32 checksum is obtained by calculating two 16-bit checksums A and B and concatenating their bits into a 32-bit integer. A is the sum of all bytes in the string, B is the sum of the individual values of A from each step. At the beginning of an Adler-32 run, A is initialized to 1, B to 0. The sums are done modulo 65521 (the largest prime number smaller than 216). The bytes are stored in network order (big endian), B occupying the two most significant bytes. The function may be expressed as A = 1 + D1 + D2 + ... + DN (mod 65521) B = (1 + D1) + (1 + D1 + D2) + ... + (1 + D1 + D2 + ... + DN) (mod 65521) = NЧD1 + (N-1)ЧD2 + (N-2)ЧD3 + ... + DN + N (mod 65521) Adler-32(D) = B * 65536 + A where D is the string of bytes for which the checksum is to be calculated, and N is the length of D.

Afficher le fichier Open project: dmitry-dedukhin/lightweight-uploader

Méthodes publiques

Méthode	Description
Equals ( object obj ) : bool	Equals determines whether two files (buffers) have the same checksum value (identical).
GetHashCode ( ) : int	GetHashCode returns hash code for this instance.
MakeForBuff ( byte bytesBuff, int length ) : bool	Calculate Adler-32 checksum for buffer
MakeForFile ( FileStream fs ) : bool	Calculate Adler-32 checksum for file
ToString ( ) : string	ToString is a method for current AdlerChecksum object representation in textual form.
operator ( ) : bool	operator!= determines whether AdlerChecksum objects are not equal.

Private Methods

Méthode	Description
MakeForBuff ( byte bytesBuff, uint unAdlerCheckSum, int length ) : bool	Calculate Adler-32 checksum for buffer

Method Details

Equals() public méthode

Equals determines whether two files (buffers) have the same checksum value (identical).

public Equals ( object obj ) : bool
obj	object	A AdlerChecksum object for comparison
Résultat	bool

GetHashCode() public méthode

GetHashCode returns hash code for this instance.

public GetHashCode ( ) : int
Résultat	int

MakeForBuff() public méthode

Calculate Adler-32 checksum for buffer

public MakeForBuff ( byte bytesBuff, int length ) : bool
bytesBuff	byte	Bites array for checksum calculation
length	int
Résultat	bool

MakeForFile() public méthode

Calculate Adler-32 checksum for file

public MakeForFile ( FileStream fs ) : bool
fs	FileStream
Résultat	bool

ToString() public méthode

ToString is a method for current AdlerChecksum object representation in textual form.

public ToString ( ) : string
Résultat	string

operator() public static méthode

operator!= determines whether AdlerChecksum objects are not equal.

public static operator ( ) : bool
Résultat	bool