(Swift 3,4,5...) 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 Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    let cert = CkoCert()!

    // LoadFromFile will load virtually any certificate format file.
    // It will auto-recognize the format and load appropiately.
    var success: Bool = cert.load(fromFile: "/Users/chilkat/testData/cer/chilkat.cer")
    if success != true {
        print("\(cert.lastErrorText!)")
        return
    }

    // Get the public key:
    var pubkey: CkoPublicKey?

    pubkey = cert.exportPublicKey()
    if cert.lastMethodSuccess == false {
        print("\(cert.lastErrorText!)")
        return
    }

    // Save to various formats:
    success = pubkey!.saveDerFile(false, path: "/Users/chilkat/testData/pubkeys/chilkat_pkcs8.der")
    if success != true {
        print("\(pubkey!.lastErrorText!)")
        pubkey = nil
        return
    }

    success = pubkey!.savePemFile(false, path: "/Users/chilkat/testData/pubkeys/chilkat.pem")
    if success != true {
        print("\(pubkey!.lastErrorText!)")
        pubkey = nil
        return
    }

    success = pubkey!.saveDerFile(true, path: "/Users/chilkat/testData/pubkeys/chilkat_pkcs1.der")
    if success != true {
        print("\(pubkey!.lastErrorText!)")
        pubkey = nil
        return
    }

    success = pubkey!.saveXmlFile("/Users/chilkat/testData/pubkeys/chilkat.xml")
    if success != true {
        print("\(pubkey!.lastErrorText!)")
        pubkey = nil
        return
    }

    pubkey = nil
    print("Public key exported to all file formats.")

}