带有 ClientCertificate 的 Webclient 下载文件答案

【问题标题】：Webclient DownloadFile with ClientCertificate带有 ClientCertificate 的 Webclient 下载文件
【发布时间】：2016-07-01 08:45:34
【问题描述】：

我正在尝试在 url 上下载 pfx 文件。在 chrome 上打开链接时，我必须选择一个证书然后登录。但是当我用 C# WebClient 尝试时，我得到了一个错误 403 "Forbidden"。

如何以编程方式指定证书或绕过此步骤？

我的代码：

using (var client = new System.Net.WebClient())
{
    client.Credentials = new System.Net.NetworkCredential(MyLogin, MyPassword);
    client.DownloadFile(MyUrl, MyFile);
}

【问题讨论】：

标签： c# certificate webclient

【解决方案1】：

我终于得到了一个解决方案：覆盖 WebClient ！

新的网络客户端：

public class MyWebClient : WebClient
{
    X509Certificate2 certificate;

    public MyWebClient(X509Certificate2 certificate)
        : base()
    {
        this.certificate = certificate;
    }

    protected override WebRequest GetWebRequest(Uri address)
    {
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(address);
        request.ClientCertificates.Add(certificate);
        request.Credentials = this.Credentials;
        return request;
    }
}

使用方法：

using (var client = new MyWebClient(MyCertificate))
{
    // optional login/password if website require both. If not, don't set the credentials
    client.Credentials = new System.Net.NetworkCredential(MyLogin, MyPassword);
    client.DownloadFile(MyUrl, MyFile);
}

【讨论】：

@MercuryX 希望对您有所帮助

【解决方案2】：

如果有人偶然发现这个问题和答案，WebClient 覆盖的实现应该只是有点不同。

public class ExtendedWebClient : System.Net.WebClient
{
    X509Certificate2 _certificate;

    public ExtendedWebClient() : base() { }

    public ExtendedWebClient(X509Certificate2 certificate) : base()
    {
        _certificate = certificate;
    }

    protected override WebRequest GetWebRequest(Uri address)
    {
        // Base method creates HttpWebRequest and sets other needed stuff like POST method or authentication/authorization headers.
        HttpWebRequest request = (HttpWebRequest)base.Create(address);
        if(_certificate!=null && address.Schema=="https")
            request.ClientCertificates.Add(_certificate);            
        return request;
    }
}

然后在通过“htttps”请求时将其用作原始文件或与客户端证书一起使用

// For download
using(var client = new ExtendedWebClient(MyCertificate))
{
    // Add anything optional like authnetication or header here.
    client.DownloadFile(MyUrl, MyFile);
}

// ...

// Or for upload
using(var client = new ExtendedWebClient(MyCertificate))
{
    // Add anything optional like authnetication or header here.
    client.UploadFile(MyUrl, "POST", MyFile);
}

【讨论】：