为什么在消息框中显示问号而不是文本

为什么它在消息框上显示问号而不是文本

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://teamxor.net/vb/tx48/"+ page);

HttpWebResponse response = (HttpWebResponse)request.GetResponse();

StreamReader sr = new StreamReader(response.GetResponseStream());

string result = sr.ReadToEnd();

Regex r = new Regex("<div>.*?</div>");
MatchCollection mr = r.Matches(result);

foreach (Match m in mr)
{
    MessageBox.Show(m.Value, "Test", MessageBoxButtons.OK, MessageBoxIcon.Information, MessageBoxDefaultButton.Button1, MessageBoxOptions.RtlReading);
}