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JavaScript

Export a Public Key as DER into a BinData

Demonstrates the Chilkat PublicKey.GetDerBd method, which writes the public key as binary DER into a BinData. The first argument selects the representation (as for GetPem) and the second is the BinData that receives the bytes (its contents are replaced).

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: The in-memory binary export: the raw DER lands in a BinData ready to hash, transmit, or hand to another API without a temporary file. It is the BinData counterpart to the text exporters, and the first argument picks the same PKCS #1 versus SubjectPublicKeyInfo structure.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

//  Load a public key to export.  LoadFromFile inspects the content, so it accepts DER, PEM, XML,
//  JWK, and other supported representations.
var pubKey = new CkPublicKey();
success = pubKey.LoadFromFile("qa_data/public.pem");
if (success == false) {
    console.log(pubKey.LastErrorText);
    return;
}

//  Write the public key as binary DER into a BinData.  The 1st argument selects the representation
//  (as for GetPem) and the 2nd is the BinData that receives the bytes (its contents are replaced).
var preferPkcs1 = false;
var bd = new CkBinData();
success = pubKey.GetDerBd(preferPkcs1,bd);
if (success == false) {
    console.log(pubKey.LastErrorText);
    return;
}

console.log("Exported " + bd.NumBytes + " DER bytes.");