Question

我想使用VB.NET（最好）或C＃通过HTTPS下载文件。

我有这个代码通过普通的HTTP下载文件：

Dim client As WebClient = New WebClient()
Dim wp As WebProxy = New WebProxy("[IP number of our proxy server]", [port number of our proxy server])
wp.Credentials = CredentialCache.DefaultCredentials
client.Proxy = wp
client.DownloadFile("http://sstatic.net/so/img/logo.png", "c:\logo.png")

这很有效。

如何更改此代码以下载存储在HTTPS服务器上的文件？我想这与添加凭据或其他东西有关。

Answer 1

<击> 您只需将该地址指向您的HTTPS资源并通知您的凭证：

client.Credentials = new NetworkCredential("username", "password"); client.DownloadFile("https://your.resource.here", @"localfile.jog")

<击>

您正在谈论如何登录受HTML表单登录保护的站点。我之前写过这段代码，你可以调整它来登录你的远程站点：Orkut Login Code

您需要牢记的事情：

如果这是一个ASP.NET站点，您需要先调用它来获取__EVENTTARGET和__EVENTARGUMENT值，因为它们需要处理您的登录回发。如果不是，请跳过此步骤。

您需要确定网站用来填充用户名和密码的名称

您必须添加CookieContainer。它会保留您的登录cookie，以便后续调用使用该经过身份验证的上下文。

毕竟，您应该能够获取远程资源并下载它

Answer 2

您需要添加证书验证程序：

// You need to call it only once in a static constructor or multiple times there is no problem
ServicePointManager.ServerCertificateValidationCallback = ValidateCertificate;

    private static bool ValidateCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
    {
        return true;
    }

在VB中：

ServicePointManager.ServerCertificateValidationCallback = AddressOf ValidateCertificate
Dim client As WebClient = New WebClient()
'...
'Your code

  Private Shared Function ValidateCertificate(sender As Object, certificate As X509Certificate, chain As X509Chain, sslPolicyErrors As SslPolicyErrors) As Boolean
        return True
  End Function

Answer 3

尝试这样的事情

        WebClient wc = new WebClient();
        wc.UseDefaultCredentials = false;

        CredentialCache creds = new CredentialCache();
        creds.Add(new Uri(url), "Basic",new NetworkCredential(username, password, domain));

        wc.Credentials = creds;
        wc.Headers.Add(HttpRequestHeader.UserAgent,"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.0.3705;");
        //wc.Headers["Accept"] = "/";

        wc.DownloadFile(url,localpath);

使用.NET（dotnet）通过HTTPS下载文件

3 个答案: