How to convert Google API Service Account certificate to base64

Recently in Google Developer Console by mistake I generated a new SSL certificate for my project’s Service Account so had to convert it again from p12 file to base64 representation and store its thumbprint separately.

Here’s how you can do it:

var cert = new X509Certificate2("project-595a8425b1d7.p12", "notasecret", X509KeyStorageFlags.Exportable);
var thumbprint = cert.Thumbprint;
var base64 = Convert.ToBase64String(cert.Export(X509ContentType.Pfx, "notasecret")); // or Pkcs12 which works as well

And just to make sure output string actually works and certificate contains private key:

var test = new X509Certificate2(Convert.FromBase64String(base64), "notasecret");
Debug.Assert(test.PrivateKey != null);