(C#) Load RSA Public Key from JWK Format (JSON Web Key)

Demonstrates how to load an RSA public key from JWK (JSON Web Key) format.

Note: This example requires Chilkat v9.5.0.66 or later.

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// Note: This example requires Chilkat v9.5.0.66 or later.
bool success;

// First build a JWK sample to load..
Chilkat.JsonObject json = new Chilkat.JsonObject();
json.UpdateString("kty","RSA");
json.UpdateString("n","33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf-kDQiNSe2ZtqC7bnIc8-KSG_qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5-UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3_Q0auBkdbDR_ES2PbgKTJdkjc_rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw");
json.UpdateString("e","AQAB");

// The JSON contains the following:
// { 
//   "kty": "RSA",
//   "n": "33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf-kDQiNSe2ZtqC7bnIc8-KSG_qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5-UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3_Q0auBkdbDR_ES2PbgKTJdkjc_rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw",
//   "e": "AQAB",
// } 

// Note: The JSON can contain other members, such as "use", "kid", or anything else.  These will be ignored.
json.EmitCompact = false;

// Show the JWK string to be loaded:
string jwkStr = json.Emit();

Chilkat.PublicKey pubKey = new Chilkat.PublicKey();
// The LoadFromString method will automatically detect the format.
success = pubKey.LoadFromString(jwkStr);
if (success != true) {
    Debug.WriteLine(pubKey.LastErrorText);
    return;
}

// OK.. the JWK is loaded.  It can be used in whatever way desired...

// The key can be retrieved in any other format, such as XML or PEM..
Debug.WriteLine(pubKey.GetXml());

// XML output:
// <RSAPublicKey>
//     <Modulus>33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw==</Modulus>
//     <Exponent>AQAB</Exponent>
// </RSAPublicKey>

// Choose PCKS1 or PCKS8 PEM format..
bool bPreferPkcs1 = false;
Debug.WriteLine(pubKey.GetPem(bPreferPkcs1));

// PEM output
// -----BEGIN PUBLIC KEY-----
// MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA33TqqLR3eeUmDtHS89qF
// 3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA
// 04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7s
// Jp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwF
// wnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUE
// f0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1W
// SwIDAQAB
// -----END PUBLIC KEY-----