(Swift 3,4,5...) RSA Encrypt with SHA-256 hash function and SHA-1 mask function

How can this Javascript be duplicated using Chilkat?

function a(e, t) {
                var r = s.pki.publicKeyFromPem(e)
                  , n = r.encrypt(t, "RSA-OAEP", {
                    md: s.md.sha256.create(),
                    mgf1: {
                        md: s.md.sha1.create()
                    }
                });
                return s.util.encode64(n)
            }

Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens, even using the same data and key, the result will be different -- but still valid. One should not expect to get the same output.

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    let pubkey = CkoPublicKey()!

    let sbPem = CkoStringBuilder()!
    var bCrlf: Bool = true
    sbPem.appendLine("-----BEGIN PUBLIC KEY-----", crlf: bCrlf)
    sbPem.appendLine("MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA33TqqLR3eeUmDtHS89qF", crlf: bCrlf)
    sbPem.appendLine("3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA", crlf: bCrlf)
    sbPem.appendLine("04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7s", crlf: bCrlf)
    sbPem.appendLine("Jp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwF", crlf: bCrlf)
    sbPem.appendLine("wnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUE", crlf: bCrlf)
    sbPem.appendLine("f0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1W", crlf: bCrlf)
    sbPem.appendLine("SwIDAQAB", crlf: bCrlf)
    sbPem.appendLine("-----END PUBLIC KEY-----", crlf: bCrlf)

    // Load the public key object from the PEM. 
    var success: Bool = pubkey.load(from: sbPem.getAsString())
    if success != true {
        print("\(pubkey.lastErrorText!)")
        return
    }

    var originalData: String? = "This is the original data to be SHA-256 hashed and RSA encrypted."

    // First we SHA-256 hash the original data.
    let crypt = CkoCrypt2()!
    crypt.hashAlgorithm = "SHA-256"
    var hashBytes: NSData
    hashBytes = crypt.hashString(originalData)

    // Now to RSA encrypt using OAEP padding with SHA-1 for the mask function.
    let rsa = CkoRsa()!
    rsa.oaepPadding = true
    rsa.oaepHash = "SHA1"
    rsa.importPublicKeyObj(pubkey)
    rsa.encodingMode = "base64"

    // Note: The OAEP padding uses random bytes in the padding, and therefore each time encryption happens,
    // even using the same data and key, the result will be different --  but still valid.  One should not expect
    // to get the same output.
    var bUsePrivateKey: Bool = false
    var encryptedStr: String? = rsa.encryptBytesENC(hashBytes, bUsePrivateKey: bUsePrivateKey)
    if rsa.lastMethodSuccess != true {
        print("\(rsa.lastErrorText!)")
        return
    }

    print("Base64 RSA encrypted output: \(encryptedStr!)")

}