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.

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

//  Load the private key from an RSA PEM file:
pkey.LoadPemFile("pvkey2_rsa.pem");

bool success;

string pkeyXml;
//  Get the private key in XML format:
pkeyXml = pkey.GetXml();

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

//  Any string argument automatically begins the 30-day trial.

success = rsa.UnlockComponent("30-day trial");
if (success != true) {
    MessageBox.Show("RSA component unlock failed");
    return;
}

//  Import the private key into the RSA component:
success = rsa.ImportPrivateKey(pkeyXml);
if (success != true) {
    MessageBox.Show(rsa.LastErrorText);
    return;
}

//  This example will sign a string, and receive the signature
//  in a hex-encoded string.  Therefore, set the encoding mode
//  to "hex":
rsa.EncodingMode = "hex";

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

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

textBox1.Text += hexSig + "\r\n";
textBox1.Refresh();

MessageBox.Show("Success!");