如何在Silverlight中使用证书的私钥对数据签名

Question

在将数据发送到服务之前，我需要对其进行签名。我是通过以下方法在Windows应用程序中完成的：

private string SignWithPfx(string data)
    {
        var path = AppDomain.CurrentDomain.BaseDirectory + "certificate.pfx";
        var password = "1234";

        var collection = new X509Certificate2Collection();

        collection.Import(path, password, X509KeyStorageFlags.Exportable);
        var certificate = collection[0];
        var publicKey = certificate.PublicKey.Key as RSACryptoServiceProvider;

        var privateKey = certificate.PrivateKey as RSACryptoServiceProvider;


        RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
        rsa.FromXmlString(certificate.PrivateKey.ToXmlString(true));

        var signature = rsa.SignData(Encoding.ASCII.GetBytes(data), CryptoConfig.MapNameToOID("SHA256"));
        return Convert.ToBase64String(signature);
    }

但是当我将其传输到Silverlight项目时，我注意到这里没有“ X509Certificate2Collection”甚至“ RSACryptoServiceProvider”！ 我该怎么办？