convert to base 64 code example

Example 1: JavaScriptSerializer() and convert to base64

class Program
{
    static void Main(string[] args)
    {
        var account = new ExternalAccount() { Name = "Someone" };
        string json = JsonConvert.SerializeObject(account);
        string base64EncodedExternalAccount = Convert.ToBase64String(Encoding.UTF8.GetBytes(json));
        byte[] byteArray = Convert.FromBase64String(base64EncodedExternalAccount);

        string jsonBack = Encoding.UTF8.GetString(byteArray);
        var accountBack = JsonConvert.DeserializeObject<ExternalAccount>(jsonBack);
        Console.WriteLine(accountBack.Name);
        Console.ReadLine();
    }
}

[Serializable]
public class ExternalAccount
{
    public string Name { get; set; }
}

Example 2: base64

function getBase64(file:any) {
    return new Promise((resolve, reject) => {
      const reader = new FileReader();
      reader.readAsDataURL(file);
      reader.onload = () => resolve(reader.result);
      reader.onerror = error => reject(error);
    });
  }