使用c#读取.p7m文件

Question

如何使用 C# 应用程序检索 .P7M 文件的所有信息。\n示例 .p7m 文件：\n如果可能，请给我代码或示例示例链接

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MIME-Version: 1.0\nContent-Type: multipart/signed; protocol="application/x-pkcs7-signature"; micalg=sha1; boundary="----6975263937A7DDC0C0034052D76E8275"\n\nThis is an S/MIME signed message\n\n------6975263937A7DDC0C0034052D76E8275\nMIME-Version: 1.0\nSubject: MVCI - Restart Needed a\nX-Relevance-Evaluation-Period: 0:0:1\nX-Relevance-Child-Evaluation-Period: 0:0:1\nContent-Type: multipart/digest; boundary="AD27641"\n\n--AD27641\n\nSubject: MVCI - Restart Needed a\nX-Relevant-When: pending restart and (not exists file "C:\\Windows\\System32\\No_Reboot.txt")\nX-Fixlet-ID: 27641\nX-Fixlet-Category: Computer Support\nX-Fixlet-Source: BigFix\nX-Fixlet-Source-Severity: Moderate\nX-Fixlet-Source-ID: <Unspecified>\nX-Fixlet-Source-Release-Date: 9/12/2006\nX-Fixlet-Download-Size: 0\nContent-Type: multipart/related; boundary="F27641"\n\n--F27641\nContent-Type: text/html; charset=us-ascii\n\n<custom>\n--F27641\nContent-id: Action1\nContent-Type: application/x-Fixlet-Windows-Shell\n\n// only run this action on computers that are not locked\ncontinue if {not locked of action lock state}\n\nrestart\naction requires restart\n\n// only run this action on computers that are not locked\ncontinue if {not locked of action lock state}\n\naction parameter query "RestartWaitTime" with description "Please enter the number of seconds to wait after warning the user before forcing a restart on the computer:"\n\nrestart {parameter "RestartWaitTime" of action}\naction requires restart\n\n--F27641--\n\n--AD27641--\n\n------6975263937A7DDC0C0034052D76E8275\nContent-Type: application/x-pkcs7-signature; name="smime.p7s"\nContent-Transfer-Encoding: base64\nContent-Disposition: attachment; filename="smime.p7s"\n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\n9ftCqSJKSeIWUk0jnQTU/pGrySOpXeJewqgRg06Sxejf\n\n------6975263937A7DDC0C0034052D76E8275--\n\n 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如果有任何建议和问题，请回复重播，然后告诉我。\我正在等待重播。

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Answer 1

作为上面发布的非自由/非开源解决方案的替代方案，我可能建议看一下我的免费/开源 S/MIME 库：MimeKit

要处理您的输入数据，您需要执行以下操作：

var entity = MimeEntity.Load (stream);

if (entity is MultipartSigned) {
    var signed = (MultipartSigned) entity;

    foreach (var signature in signed.Verify ()) {
        try {
            bool valid = signature.Verify ();

            // If valid is true, then it signifies that the signed content has
            // not been modified since this particular signer signed the content.
            //
            // However, if it is false, then it indicates that the signed content
            // has been modified.
        } catch (DigitalSignatureVerifyException) {
            // There was an error verifying the signature.
        }

        // If you'd like to get a copy of the certificate used for signing,
        // you could do this:
        var wrapper = (SecureMimeDigitalCertificate) signature.Certificate;
        var cert = wrapper.Certificate;

        // The cert is a BouncyCastle X509Certificate, so if you want to convert
        // it to a System.Security X509Certificate2, you can do this:
        var x509certificate2 = new X509Certificate2 (cert.GetEncoded ());
    }
}