C#

Example: Hash Text in Chunks

Shows how to generate a final hash, like SHA-256, for a large text by processing it in chunks. C#

bool success = false;

Chilkat.Crypt2 crypt = new Chilkat.Crypt2();
crypt.HashAlgorithm = "sha256";
crypt.Charset = "utf-8";

Chilkat.BinData bd = new Chilkat.BinData();

string s = "The quick brown fox jumped over the lazy dog.\r\n";

//  Accumulate the text in a StringBuilder.  We'll demonstrate hashing the text in chunks,
//  and then also hashing the entire text at once to show the results are the same.

bd.AppendString(s,"utf-8");
success = crypt.HashBeginString(s);

int i = 0;
while (i < 200) {
    bd.AppendString(s,"utf-8");
    crypt.HashMoreString(s);
    i = i + 1;
}

//  Get the hash in base64 format.
crypt.EncodingMode = "base64";

string encodedHash = crypt.HashFinalENC();
Debug.WriteLine("Hash computed in chunks: " + encodedHash);

//  Let's alternatively compute the hash of the entire amount of data at once,
//  to show the hash computation is the same:
encodedHash = crypt.HashBdENC(bd);
Debug.WriteLine("Hash computed in 1 step: " + encodedHash);

//  Output:

//  Hash computed in chunks: unwkVff61k40roRIJizaknreScHaL6frWe37kydXbZQ=
//  Hash computed in 1 step: unwkVff61k40roRIJizaknreScHaL6frWe37kydXbZQ=