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<hr><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">The HTTP library allows access to Internet resources using the HTTP protocol.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">Communication is done with two objects; WebRequest which makes the request and
WebResponse which includes the data received from the server (like a html file).</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">The stages of communicating with a HTTP server are:</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">- Create a WebRequest object with the required URL.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">- Set the WebRequest header properties.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">- If you need to upload data with the request use WebRequest.GetStream and write to the
stream.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">- Launch the request and assign the response to a WebResult object.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">The last operation blocks until the data is received.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">- Use the WebResult.GetStream to get the data stream and read the result from it.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">- Close the WebResult.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101"><br></span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">As of version 1.5 it is possible to make asynchronous requests using
WebRequest.GetAsyncResponse, and it is possible to retrieve the data asynchronously
with WebResponse.GetAsyncStream or WebResponse.GetAsyncString.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">Unlike the synchronous calls the asynchronous calls will not freeze the interface during
communication.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101"><br></span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">This help manual doesn't cover the HTTP protocol.</span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">The HTTP protocol specifications can be found here: </span></font><a href="http://www.w3.org/Protocols/rfc2616/rfc2616.html"><font face="Times New Roman" color="#0000ff"><span style=" font-size:12pt; font-family:Times New Roman; color:#0000ff"><u>http://www.w3.org/Protocols/rfc2616/rfc2616.html</u></span></font></a></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">Another useful resource: </span></font><a href="http://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol"><font face="Times New Roman" color="#0000ff"><span style=" font-size:12pt; font-family:Times New Roman; color:#0000ff"><u>http://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol</u></span></font></a></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101"><br></span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101">The following code is an example of some usages of the HTTP library:</span></font></div><div align="left"><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Request is a WebRequest object, Response is a WebResponse object</span></font></div><div align="left"><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Reader and Writer are BinaryFile objects.</span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Sub </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">Globals</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">dim </span></font><font face="Courier New" color="#010101" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#010101">Buffer(0) </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">as </span></font><font face="Courier New" color="#010101" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#010101">byte</span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">End</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Sub</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"><br></span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Sub </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">App_Start</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Form1.Show</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> URL = "http://www.basic4ppc.com/forum/images/Basic4ppc2.gif"</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> DownloadFile(</span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">AppPath</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> & "\NewImage.gif",URL)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Form1.Image = "NewImage.gif"</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> URL = "http://en.wikipedia.org/wiki/HTTP"</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> TextBox1.Text = GetText(URL) </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'TextBox1 is
a multiline textbox.</span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">End</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Sub</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"><br></span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Sub</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> GetText (URL)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Response.New1</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Request.New1(URL)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Response.Value = Request.GetResponse </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'This
line calls the server
and gets the response.</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> string = Response.GetString </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Get the Response
string.</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Response.Close</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">return</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> string</span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">End</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Sub</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"><br></span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Sub </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">UploadFile (UploadFile, URL) </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Requires a server with write
permission.</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Response.New1</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Request.New1(URL)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Request.Method = "PUT"</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Writer.New1(Request.GetStream,true) </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Use
a BinaryFile object to
write the data to the Request stream.</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">dim </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">Buffer(4096) </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">as </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">byte</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">FileOpen</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">(c1,UploadFile,cRandom)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Reader.New1(c1,true) </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Reads the local file.</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> count = Reader.ReadBytes(buffer(),4096) </span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Do While </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">count > 0</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Writer.WriteBytes2(buffer(),0,count)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> count = Reader.ReadBytes(buffer(),4096)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">loop</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">FileClose</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">(c1)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Request.GetResponse </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Launch the request (upload
the file).</span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">End Sub</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"><br></span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Sub </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">DownloadFile (LocalFile,URL)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Response.New1</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Request.New1(URL)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Response.Value = Request.GetResponse </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Launch
the request and get
the response.</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Msgbox</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">("Download size: " & Response.ContentLength) </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Show the file
size.</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Reader.New1(Response.GetStream,true) </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Use
a BinaryFile object to
read the data from the Response stream.</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">FileOpen</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">(c1,LocalFile,cRandom)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Writer.New1(c1,false)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">dim </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">buffer(4096) </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">as </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">byte</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> count = Reader.ReadBytes(buffer(),4096)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">do while </span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">count > 0</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Writer.WriteBytes2(buffer(),0,count)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> count = Reader.ReadBytes(buffer(),4096)</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">loop</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">FileClose</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">(c1) </span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> Response.Close </span></font><font face="Courier New" color="#008000" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#008000">'Close the Response stream.</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"> </span></font><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">Msgbox</span></font><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000">("File saved.")</span></font></div><div align="left"><font face="Courier New" color="#0000ff" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#0000ff">End Sub</span></font></div><div align="left"><font face="Courier New" size="2"><span style=" font-size:10pt; font-family:Courier New; color:#000000"><br></span></font></div><div align="left"><font face="Times New Roman" color="#010101"><span style=" font-size:12pt; font-family:Times New Roman; color:#010101"><br></span></font></div><div align="left"> </div>
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