(Visual FoxPro) Convert RSA Private Key to Public Key

Demonstrates how to get a public RSA key from a private RSA key.

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL lnSuccess
LOCAL loPrivKey
LOCAL loPubKey
LOCAL lnBPreferPkcs1

lnSuccess = 0

loPrivKey = CreateObject('Chilkat.PrivateKey')

* Step 1: Load the private key from a source.
* (Chilkat can load private keys from all types of formats, and from in-memory bytes or encoded strings.
* see the online reference documentation for more options.)
lnSuccess = loPrivKey.LoadPemFile("qa_data/pem/VP_Private.pem")
IF (lnSuccess = 0) THEN
    ? loPrivKey.LastErrorText
    RELEASE loPrivKey
    CANCEL
ENDIF

* Step 2: Get the public key object from the private key object.
loPubKey = CreateObject('Chilkat.PublicKey')
loPrivKey.ToPublicKey(loPubKey)

* Step 3: Save the public key in a desired format. 
* (Chilkat can load or save public and private keys in many different formats.  See
* the online reference documentation for more options.)

* Saves to a PKCS8 PEM file.
lnBPreferPkcs1 = 0
lnSuccess = loPubKey.SavePemFile(lnBPreferPkcs1,"qa_data/pem/VP_Public.pem")
IF (loPubKey.LastMethodSuccess = 0) THEN
    ? loPubKey.LastErrorText
    RELEASE loPrivKey
    RELEASE loPubKey
    CANCEL
ENDIF

? "Extracted and saved public key from private key."

RELEASE loPrivKey
RELEASE loPubKey