(Visual Basic 6.0) Export Digital Certificate's Public Key

The ExportPublicKey method can be called to get a certificate's public key. It can then be saved to any of a number of formats: (1) OpenSSL DER, (2) OpenSSL PEM, (3) RSA DER, (4) XML.

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

Dim cert As New ChilkatCert

' LoadFromFile will load virtually any certificate format file.
' It will auto-recognize the format and load appropiately.
Dim success As Long
success = cert.LoadFromFile("/Users/chilkat/testData/cer/chilkat.cer")
If (success <> 1) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

' Get the public key:
Dim pubkey As PublicKey

Set pubkey = cert.ExportPublicKey()
If (cert.LastMethodSuccess = 0) Then
    Debug.Print cert.LastErrorText
    Exit Sub
End If

' Save to various formats:
success = pubkey.SaveDerFile(0,"/Users/chilkat/testData/pubkeys/chilkat_pkcs8.der")
If (success <> 1) Then
    Debug.Print pubkey.LastErrorText

    Exit Sub
End If

success = pubkey.SavePemFile(0,"/Users/chilkat/testData/pubkeys/chilkat.pem")
If (success <> 1) Then
    Debug.Print pubkey.LastErrorText

    Exit Sub
End If

success = pubkey.SaveDerFile(1,"/Users/chilkat/testData/pubkeys/chilkat_pkcs1.der")
If (success <> 1) Then
    Debug.Print pubkey.LastErrorText

    Exit Sub
End If

success = pubkey.SaveXmlFile("/Users/chilkat/testData/pubkeys/chilkat.xml")
If (success <> 1) Then
    Debug.Print pubkey.LastErrorText

    Exit Sub
End If

Debug.Print "Public key exported to all file formats."