在C#中處理Response的編碼問題可以通過以下幾種方式：

1. 使用WebClient類獲取Response，并設置相應的編碼格式：

WebClient client = new WebClient();
client.Encoding = Encoding.UTF8; // 設置編碼格式為UTF-8
string response = client.DownloadString("http://example.com");

2. 使用HttpWebRequest類獲取Response，并設置相應的編碼格式：

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://example.com");
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream stream = response.GetResponseStream();
StreamReader reader = new StreamReader(stream, Encoding.UTF8); // 設置編碼格式為UTF-8
string responseData = reader.ReadToEnd();

3. 如果Response的編碼格式不確定，可以通過檢查Response的Content-Type頭部來獲取編碼格式，并根據其值解析Response：

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://example.com");
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
string contentType = response.ContentType;
Encoding encoding = Encoding.GetEncoding("utf-8");

if (!string.IsNullOrEmpty(contentType))
{
    Match match = Regex.Match(contentType, "charset=([A-Za-z0-9-]+)");
    if (match.Success)
    {
        encoding = Encoding.GetEncoding(match.Groups[1].Value);
    }
}

StreamReader reader = new StreamReader(response.GetResponseStream(), encoding);
string responseData = reader.ReadToEnd();

通過以上方法，可以有效處理Response的編碼問題，確保正確解析Response的內容。