I use System.Net.WebClient.DownloadString(url) to get the HTML source of http://kqxs.vn but what I recieved is a caution text from the web server which says in Vietnamese as:
"Xin loi. Chung toi khong the dap ung yeu cau truy cap cua ban... Vui long lien he :
[email protected]. Chao ban"
which is translated in English as
"Sorry. We cannot response to your request... Please contact... Good bye."
This is strange because when I use a WebControl to get the HTML ( by calling .Navigate(url) and then .DocumentText), I receive the different HTML codes - which in turn is exactly what I see when open the website by Firefox & view the source code from Firefox.
I read DownloadData() is downloading source that is completely wrong. Source view in Firefox different than that downloaded. - Stack Overflow and found the answer to my symptom. But I don't know how to set the User-Agent. Please help.