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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);