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Swift Requires Chilkat v11.0.0+

Convert RSA Private Key to Public Key

See more RSA Examples

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

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Swift

func chilkatTest() {
    var success: Bool = false

    let privKey = CkoPrivateKey()!

    //  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.)
    success = privKey.loadPemFile(path: "qa_data/pem/VP_Private.pem")
    if success == false {
        print("\(privKey.lastErrorText!)")
        return
    }

    //  Step 2: Get the public key object from the private key object.
    let pubKey = CkoPublicKey()!
    privKey.toPublicKey(pubKey: pubKey)

    //  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.
    var bPreferPkcs1: Bool = false
    success = pubKey.savePemFile(preferPkcs1: bPreferPkcs1, path: "qa_data/pem/VP_Public.pem")
    if pubKey.lastMethodSuccess == false {
        print("\(pubKey.lastErrorText!)")
        return
    }

    print("Extracted and saved public key from private key.")

}