问题

I'm here to provide translations for the code-related content you've provided. Here's the translated code portion:

我正在尝试获得最小的RSA密钥对文件大小，以便在QR码上进行额外加密保存。我希望大小尽可能接近默认的2048位，但不幸的是，我只能导出带有附加的CRT数据，这仅用于加快计算速度。对我来说，大小比速度更重要。

我正在使用BouncyCastle并成功创建了一个`AsymmetricCipherKeyPair`。我成功获取了“过大”的私钥，方法如下：

```java
AsymmetricKeyParameter rsaPri = res.Private;
PrivateKeyInfo p = PrivateKeyInfoFactory.CreatePrivateKeyInfo(rsaPri);
byte[] piby = p.Attributes.GetEncoded();

其中res等于提到的AsymmetricCipherKeyPair。

如何仅获取e、N和d、N从密钥对中？

此外，如何再次导入它？

我已经进行了多个小时的研究，但我很难理解它。

任何帮助都将不胜感激

Please note that the translation is provided for the code portion, as you requested. If you have any further code-related questions or need assistance with a specific part of the code, please feel free to ask.

<details>
<summary>英文:</summary>

I&#39;m trying to get the smallest rsa key pair file size possible to save with extra encryption on a QR-Code. I&#39;d like the size to be as close as possible to the default 2048 bits, but unfortunatly I&#39;ve only managed to export it with the additional CRT-Data, which is only usefull for faster calculation. To me size is more important than speed.

I&#39;m using BouncyCastle and managed to create an `AsymmetricCipherKeyPair`. The &quot;oversized&quot; Private Key i managed to get by using:

AsymmetricKeyParameter rsaPri = res.Private;
PrivateKeyInfo p = PrivateKeyInfoFactory.CreatePrivateKeyInfo(rsaPri);
byte[] piby = p.Attributes.GetEncoded();

Where res is equal to the mentioned `AsymmetricCipherKeyPair`

How can I achieve only getting e,N and d,N from Keypair?

And further more, how can I import it again?

I've done multiple hours of research but I'm strugging to wrap my head around it.

Any assistance is apprechiaded :)

</details>


# 答案1
**得分**: 1

"如预期，有一种简单的方法可以做到这一点：正如progman所述，可以轻松地将`AsymmetricKeyParameter`解析为`RsaKeyParameters`并提取我正在寻找的值。"

<details>
<summary>英文:</summary>

as expected there is an easy way of doing this: as progman stated, one can easily parse the `AsymmetricKeyParameter` as `RsaKeyParameters` and extract the values I was looking for.

</details>