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C#

RSA Signature SHA256withRSA, iso-8859-1, base64

See more RSA Examples

RSA sign the iso-8859-1 byte representation of a string with SHA256withRSA, and return the signature in the base64 encoding.

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C#
bool success = false;

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  This example will duplicate the following Java code:
//  
//  Signature sign = Signature.getInstance("SHA256withRSA");
//  sign.initSign(privateKey);
//  sign.update(original.getBytes(Charset.forName("ISO-8859-1")));
//  
//  ...
//  byte[] resultado = sign.sign();
//  sello = encodeByteArrayToBase64(resultado);
//  

//  Load an RSA private key for signing.
//  You can load any format file.  This example loads a .pem, but you can provide path to any type of file holding a private key.
Chilkat.PrivateKey privKey = new Chilkat.PrivateKey();
success = privKey.LoadAnyFormatFile("qa_data/pem/rsa_passwd.pem","passwd");
if (success == false) {
    Debug.WriteLine(privKey.LastErrorText);
    return;
}

Chilkat.Rsa rsa = new Chilkat.Rsa();
rsa.UsePrivateKey(privKey);

string originalData = "This is the string to be hashed an RSA signed.";

//  Indicate that we want the iso-8859-1 byte representation of the string to be signed
rsa.Charset = "iso-8859-1";

//  We want the RSA signature in base64 format
rsa.EncodingMode = "base64";

string sigBase64 = rsa.SignStringENC(originalData,"sha256");
Debug.WriteLine(sigBase64);