在下載程式碼之前加入如下程式碼：

// 解決WebClient不能通過https下載內容問題
System.Net.ServicePointManager.ServerCertificateValidationCallback +=
	delegate(object sender, System.Security.Cryptography.X509Certificates.X509Certificate certificate,
	         System.Security.Cryptography.X509Certificates.X509Chain chain,
	         System.Net.Security.SslPolicyErrors sslPolicyErrors)
{
	return true; // **** Always accept
};
 

上述程式碼主要是為了跳過https的ssl驗證。

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