asp.net HttpWebRequest Automatic Identification page Coding _ Practical Skills

Copy Code code as follows:

static string getencoding (string url)
{
HttpWebRequest request = null;
HttpWebResponse response = null;
StreamReader reader = null;
Try
{
Request = (HttpWebRequest) webrequest.create (URL);
Request. Timeout = 20000;
Request. AllowAutoRedirect = false;

Response = (HttpWebResponse) request. GetResponse ();
if (response. StatusCode = = Httpstatuscode.ok && response. ContentLength < 1024 * 1024)
{
if (response. ContentEncoding!= null && response. Contentencoding.equals ("gzip", Stringcomparison.invariantcultureignorecase))
reader = new StreamReader (response, new GZipStream. GetResponseStream (), compressionmode.decompress));
Else
reader = new StreamReader (response. GetResponseStream (), encoding.ascii);

string html = reader. ReadToEnd ();

Regex reg_charset = new Regex (@ "charset\b\s*=\s* (? <charset>[^" "]*)");
if (Reg_charset. IsMatch (HTML))
{
Return Reg_charset. Match (HTML). Groups["CharSet"]. Value;
}
else if (response. CharacterSet!= String. Empty)
{
return response. CharacterSet;
}
Else
return Encoding.Default.BodyName;
}
}
Catch
{
}
Finally
{

if (response!= null)
{
Response. Close ();
Response = NULL;
}
if (reader!= null)
Reader. Close ();

if (Request!= null)
request = NULL;

}

return Encoding.Default.BodyName;
}

<summary>
Get Source code
</summary>
<param name= "url" ></param>
<returns></returns>
static string gethtml (string url, Encoding Encoding)
{
HttpWebRequest request = null;
HttpWebResponse response = null;
StreamReader reader = null;
Try
{
Request = (HttpWebRequest) webrequest.create (URL);
Request. Timeout = 20000;
Request. AllowAutoRedirect = false;

Response = (HttpWebResponse) request. GetResponse ();
if (response. StatusCode = = Httpstatuscode.ok && response. ContentLength < 1024 * 1024)
{
if (response. ContentEncoding!= null && response. Contentencoding.equals ("gzip", Stringcomparison.invariantcultureignorecase))
reader = new StreamReader (response, new GZipStream. GetResponseStream (), compressionmode.decompress), encoding);
Else
reader = new StreamReader (response. GetResponseStream (), encoding);
string html = reader. ReadToEnd ();

return HTML;
}
}
Catch
{
}
Finally
{

if (response!= null)
{
Response. Close ();
Response = NULL;
}
if (reader!= null)
Reader. Close ();

if (Request!= null)
request = NULL;

}

return string. Empty;
}