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Convert RSA Private Key to Public Key

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

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Local $bSuccess = False

$oPrivKey = ObjCreate("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.)
$bSuccess = $oPrivKey.LoadPemFile("qa_data/pem/VP_Private.pem")
If ($bSuccess = False) Then
    ConsoleWrite($oPrivKey.LastErrorText & @CRLF)
    Exit
EndIf

; Step 2: Get the public key object from the private key object.
$oPubKey = ObjCreate("Chilkat.PublicKey")
$oPrivKey.ToPublicKey($oPubKey)

; 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.
Local $bPreferPkcs1 = False
$bSuccess = $oPubKey.SavePemFile($bPreferPkcs1,"qa_data/pem/VP_Public.pem")
If ($oPubKey.LastMethodSuccess = False) Then
    ConsoleWrite($oPubKey.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite("Extracted and saved public key from private key." & @CRLF)