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C#

Create PKCS1 RSA Signature with PEM Private Key

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Demonstrates how to load a private key from a PEM file and create a PKCS1 RSA digital signature.

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C#
bool success = false;

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

Chilkat.PrivateKey pkey = new Chilkat.PrivateKey();

// Load the private key from an RSA PEM file:
success = pkey.LoadPemFile("pvkey2_rsa.pem");
if (success == false) {
    Debug.WriteLine(pkey.LastErrorText);
    return;
}

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

// Import the private key into the RSA object:
success = rsa.UsePrivateKey(pkey);
if (success == false) {
    Debug.WriteLine(rsa.LastErrorText);
    return;
}

// Get the signature as hex.
rsa.EncodingMode = "hex";

string strData = "This is the string to be signed.";

// Sign the string using the sha-1 hash algorithm.
// Other valid choices are "md2", "md5", "sha256",
// "sha384", and "sha512".
string hexSig = rsa.SignStringENC(strData,"sha-1");

Debug.WriteLine(hexSig);

Debug.WriteLine("Success!");