Use of the HttpWebRequest class and WebRequest class

1. System. Net. HttpWebRequest class
Http://msdn.microsoft.com/library/chs/default.asp? Url =/library/CHS/cpref/html/frlrfsystemnetwebrequestclasstopic. asp

The following code sends data in Post mode:
Using System. IO;
Using System. Net;
Using System. Text;
Using System. Text. RegularExpressions;

Private void btnConfirm_Click (object sender, System. EventArgs e)
{
String UserName = txtUserName. Text;
String SpotID = txtSpotID. Text;
String BBS = txtBBS. Text;
String Board = txtBoard. Text;
String Title = txtTitle. Text;
String Content = txtContent. Text;
Content = NoHTML (Content); // remove HTML tags
String UserIp = Request. ServerVariables ["REMOTE_HOST"]. ToString ();
String PostUrl = "";
String PostDateTime = DateTime. Now. ToString ();

String WebSite = ""; // server receiving page
WebSite = System. Configuration. ConfigurationSettings. receivettings ["PostUrl"];

String strQuery = "UserName =" + UserName + "& SpotID =" + SpotID + "& BBS =" + BBS + "& Board =" + Board +
"& Title =" + Title + "& Content =" + Content + "& UserIp =" + UserIp + "& PostUrl =" + PostUrl + "& PostDateTime =" + PostDateTime; // data parameter queue
Encoding encoding = Encoding. UTF8;
Byte [] data = encoding. GetBytes (strQuery );

// Prepare the request...
HttpWebRequest myRequest = (HttpWebRequest) WebRequest. Create (WebSite );
MyRequest. Method = "POST ";
MyRequest. ContentType = "application/x-www-form-urlencoded ";
MyRequest. ContentLength = data. Length;
Stream newStream = myRequest. GetRequestStream ();
// Send data
NewStream. Write (data, 0, data. Length );
NewStream. Close ();

Page. RegisterStartupScript ("script", GetShowAlert ("published successfully! "," Window. location. href ('clientpostnote. aspx ');"));
}

/// <Summary>
/// Remove HTML tags
/// </Summary>
/// <Param name = "Htmlstring"> including the source code of HTML </param>
/// <Returns> removed text </returns>
Public string NoHTML (string Htmlstring)
{
// Delete the script
Htmlstring = Htmlstring. Replace ("\ r \ n ","");
Htmlstring = Regex. Replace (Htmlstring, @ "<script .*? </Script> "," ", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "<style .*? </Style> "," ", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "<. *?> "," ", RegexOptions. IgnoreCase );
// Delete HTML
Htmlstring = Regex. Replace (Htmlstring, @ "<(. [^>] *)>", "", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "([\ r \ n]) [\ s] +", "", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "-->", "", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "<! --. * "," ", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "& (quot | #34);", "\" ", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "& (amp | #38);", "&", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "& (lt | #60);", "<", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "& (gt | #62);", ">", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "& (nbsp | #160);", "", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "& (iexcl | #161);", "\ xa1", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "& (cent | #162);", "\ xa2", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "& (pound | #163);", "\ xa3", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "& (copy | #169);", "\ xa9", RegexOptions. IgnoreCase );
Htmlstring = Regex. Replace (Htmlstring, @ "(\ d +);", "", RegexOptions. IgnoreCase );
Htmlstring = Htmlstring. Replace ("<","");
Htmlstring = Htmlstring. Replace ("> ","");
Htmlstring = Htmlstring. Replace ("\ r \ n ","");
Htmlstring = HttpContext. Current. Server. HtmlEncode (Htmlstring). Trim ();
Return Htmlstring;
}

Public string GetShowAlert (string info, string action)
{
String strScript = String. Empty;
StrScript = "<script language = javascript> \ r \ n ";
StrScript + = "document. onreadystatechange = ShowAlert; \ r \ n ";
StrScript + = "function ShowAlert () \ r \ n ";
StrScript + = "{\ r \ n ";
StrScript + = "if (document. readyState = \" complete \ ") \ r \ n ";
StrScript + = "{\ r \ n ";
StrScript + = "alert ('" + info. replace ("'",""). replace ("\ n ",""). replace ("\ r", "") + "'); \ r \ n ";
If (action. Length> 0)
{
If (action [action. Length-1]! = ';')
Action = action + ";";
StrScript + = action + "\ r \ n ";
}
StrScript + = "} \ r \ n ";
StrScript + = "} \ r \ n ";
StrScript + = "</script> ";
Return strScript;
}

2. System. Net. WebRequest class
Http://msdn.microsoft.com/library/chs/default.asp? Url =/library/CHS/cpref/html/frlrfsystemnetwebrequestclasstopic. asp

The following code sends data asynchronously in Get mode:
Using System. IO;
Using System. Net;
Using System. Text. RegularExpressions;
Private void btnConfirm_Click (object sender, System. EventArgs e)
{
String UserName = txtUserName. Text;
String SpotID = txtSpotID. Text;
String BBS = txtBBS. Text;
String Board = txtBoard. Text;
String Title = txtTitle. Text;
String Content = NoHTML (txtContent. Text );
String UserIp = Request. ServerVariables ["REMOTE_HOST"]. ToString ();
String PostUrl = "";
String PostDateTime = DateTime. Now. ToString ();

String noteinfo = ""; // post content
Noteinfo = "post content :"
+ "\ R \ n UserName:" + UserName + "\ r \ n Website:" + SpotID + "\ r \ n Forum:" + BBS
+ "\ R \ n Forum:" + Board + "\ r \ n Title:" + Title + "\ r \ n Content:" + Content
+ "\ R \ n IP:" + UserIp + "\ r \ n URL:" + PostUrl + "\ r \ n ";

String WebSite = ""; // server receiving page
WebSite = System. Configuration. ConfigurationSettings. receivettings ["PostUrl"];
String Parameters = "UserName; SpotID; BBS; Board; Title; Content; UserIp; PostUrl; PostDateTime ";
String ParameterValues = UserName + ";" + SpotID + ";" + BBS + ";" + Board + ";" + Title + ";" + Content + "; "+ UserIp +"; "+ PostUrl +"; "+ PostDateTime;

BLLPostData (noteinfo, WebSite, Parameters, ParameterValues); // asynchronous Post Data

Page. RegisterStartupScript ("script", GetShowAlert ("published successfully! "," Window. location. href ('addnotenet. aspx ');"));
}

Public void BLLPostData (string noteinfo, string WebSite, string Parameters, string ParameterValues)
{
BLLPostDataDeal (noteinfo, WebSite, Parameters, ParameterValues );
}
/// <Summary>
/// Asynchronous Post Data
/// </Summary>
Private void BLLPostDataDeal (string noteinfo, string WebSite, string Parameters, string ParameterValues)
{
AsyncPostDataDeal asynci = new AsyncPostDataDeal (AsPostDataDeal );
// AsyncCallback cb = new AsyncCallback (Results );
// IAsyncResult ar = asynci. BeginInvoke (PhoneNo, LoginName, Mobile, CusID, XMLData, cb, asynci );

// No callback delegate is provided when asynchronous calls are started.
IAsyncResult ar = asynci. BeginInvoke (noteinfo, WebSite, Parameters, ParameterValues, null, asynci );
}
Public delegate void AsyncPostDataDeal (string noteinfo, string WebSite, string Parameters, string ParameterValues );
Private void AsPostDataDeal (string noteinfo, string WebSite, string Parameters, string ParameterValues)
{
String msg = ""; // log
Try
{
If (WebSite! = "")
{
String RegResult = ""; // receives the returned value
RegResult = ConnectToWebSite2 (WebSite, Parameters, ParameterValues );
// Int IsSuccess =-1; // receiving status

If (RegResult = "Y ")
{
// IsSuccess = 1;
Msg = DateTime. Now. ToString () + "post transfer successful! \ R \ n "+ noteinfo;
Log (msg );
}
Else if (RegResult = "N ")
{
// IsSuccess = 0;
Msg = DateTime. Now. ToString () + "data insertion error. Transmission failed! \ R \ n "+ noteinfo;
Log (msg );
}
Else if (RegResult = "F ")
{
// IsSuccess = 2;
Msg = DateTime. Now. ToString () + "An error occurred on the server and the transfer failed! \ R \ n "+ noteinfo;
Log (msg );
}
}
Else
{
Msg = DateTime. Now. ToString () + "the transmission URL is not obtained. Transmission cannot continue! \ R \ n "+ noteinfo;
Log (msg );
}
}
Catch (Exception ex)
{
Msg = DateTime. Now. ToString () + "transmission failed! The error is as follows: "+ ex. Message +" \ r \ n "+ noteinfo;
Log (msg );
}
}

/// <Summary>
/// Use the specified parameter (";") to access the specified URL
/// </Summary>
/// <Param name = ""> </param>
/// <Param name = "parameter name"> </param>
/// <Param name = "parameter value"> </param>
/// <Returns> </returns>
Public string ConnectToWebSite2 (string Web, string Parameters, string ParameterValues)
{
String sPageText = "";

Stream responseStream = null;
StreamReader reader = null;

Web + = "? 1 = 1 ";

If (Parameters. Trim () = "" | ParameterValues. Trim () = "")
{
Log ("the parameter or parameter value is not specified. Please confirm! ");
}
Else
{
String Delimeter = ";";
String [] aryParm = Parameters. Split (Delimeter. ToCharArray ());
String [] aryParmValue = ParameterValues. Split (Delimeter. ToCharArray ());

If (aryParm. Length! = AryParmValue. Length)
{
Log ("the number of parameters and the number of parameter values are not equal. Please confirm! ");
}
Else
{
For (int I = 0; I <aryParm. Length; I ++)
{
AryParmValue [I] = System. Web. HttpUtility. UrlEncode (aryParmValue [I]. ToString ());
Web + = "&" + aryParm [I]. Trim () + "=" + aryParmValue [I]. Trim ();
}
System. Uri RegUri = new Uri (Web );
WebRequest request = WebRequest. Create (RegUri );
WebResponse response = request. GetResponse ();
Try
{
ResponseStream = response. GetResponseStream ();
Reader = new StreamReader (responseStream, System. Text. Encoding. Default );
SPageText = reader. ReadToEnd ();
}
Finally
{
Reader. Close ();
ResponseStream. Close ();
Response. Close ();
}
}
}
Return sPageText;
}

Public void Log (string logText)
{
String strPath = AppDomain. CurrentDomain. BaseDirectory + @ "\ Log ";
If (! System. IO. Directory. Exists (strPath ))
{
System. IO. Directory. CreateDirectory (strPath );
}

StreamWriter sw = null;
String fileName = strPath + @ "\ log.txt ";
If (File. Exists (fileName ))
{
Sw = File. AppendText (fileName );
}
Else
{
Sw = new StreamWriter (fileName );
}
Sw. WriteLine (logText );
Sw. Close ();
}