Organising Communication with WinSocket

<p><font face="Verdana, Arial, Helvetica, sans-serif" size="3" color="#000000"><b>Organising 
 Communication with WinSock</b></font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><b>[Introduction] 
 </b><br>
 </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">Hi. 
 This is my first tutorial so it may be a little bad, but I hope I can help you 
 out a little. This tutorial is for basic to intermediate coders and will explain 
 a little on communication between 2 programs such as a chat program. Now you 
 may have seen a lot of chat programs on here some are good some are just basic 
 and ONLY do chat, in the latter the two programmes will be just sending text 
 between one another. This tutorial will teach you how to organise your data 
 packets and allow your chat program (or any other type of communication program) 
 to do a lot more that just send text.<br>
 <br>
 Notice: I'm sorry that teh code is not indented properly. dam word doesnt copy 
 and paste properly and I can add spaces using dream weaver so I hope you can 
 make do. <br>
 </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#0000FF">Updated 
 Data is in Blue: This Information is for new coders that dont quite understand 
 what I'm doing and I think if I was in there shoes I would agree with them. 
 The sections in blue will explain what exactly we are doing and how to do it.</font></p>
<font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#0000FF"><b>I 
have included a fully documented example project that will help you see what is 
going on in the code and how it all works. </b></font> 
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#0000FF">What 
 we are going to do. We are going to start off by learning how data packets are 
 formed or better put, how you the coder should organise the information you 
 tell your programs to tell each other. Then we will cover how to make your datatypes. 
 These datatypes hold the key to the data and allow the program to understand 
 exaclty what is has been given. thirdly we will cover how to make sending packets 
 of data faster and easier in the long run. we will then learn how to unscramble 
 merged data that can be a problems for both new and experenced Programmers. 
 We will then learn how out programs can quickly and easilly decipher what it 
 has been given. </font><br>
 <br>
 <font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><font color="#0000FF">NOTE: 
 the code in this artical is related to Visual Basic Version 5 and 6. it has 
 not been tested for any other platform</font></font><br>
 <br>
 <font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"> 
 </font><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"> 
 Okay so lets begin. First off let me explain how I organise my data packets</font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"> 
 <b>[Data Packet Structure] </b></font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">When 
 my chat program sends data the data is in 2 parts, the Data Type and the Data. 
 For example: </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">¬04HELLO! 
 </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">Part 
 1 (Data Type): </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">The 
 first two numbers tells the recipient program what the data is. Say if the number 
 is 04 then it could mean, "Here is a message for you" or if its 07 the it could 
 mean "My nick name is: " </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">Part 
 2 (Data) </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">This 
 is the data that goes with the packet. What the recipient program does with 
 it is dependant on the Data Type </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">You 
 may have noticed the "¬" symbol. Don't worry its actually part 
 of the data packet and not another instance of bad English / Typing. All will 
 be relieved later on. <br>
 </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><b>[Setting 
 the Types] </b><br>
 </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">Okay 
 so now we know how the packets are formed. Now we need to code the data types 
 so that its easier later on to do stuff. Here is how you would set your data 
 types in a module file (or whatever). </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#0000FF">A 
 Module file is a file that is used to store code. It allows coders to organise 
 files alot easier and put certain code into certain, relivent files. To create 
 a module file goto to the menu bar, choose "Project" then choose "Add 
 module".<br>
 <br>
 </font><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">=================== 
 </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#666666">Public 
 Enum DataTypes<br>
 MESSAGE = 0 <br>
 NICKNAME = 1<br>
 End enum </font><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><br>
 <br>
 =================== <br>
 <br>
 <font color="#0000FF">An Enum is like the type Boolean (True or false) with 
 boolean if you choose TRUE then the number is set to 1 becuase that is how its 
 defined. it you choose FALSE then the number is set to 0. With the Enum statement 
 we can make our very own boolean type, type. <br>
 <br>
 Okay so you've entered in the code above, now we have a type called DataTypes, 
 to test it hit the enter button and type<br>
 <br>
 <font color="#666666">DIM TESTVARABLE as DataTypes</font></font></font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#0000FF">Now 
 type in</font><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"> 
 <font color="#666666">TESTVARABLE = <font color="#0000FF">now a menu should 
 come down and you can select which one you want and it will right it in for 
 you. </font></font><br>
 <br>
 I'm not going to put a lot of types on here. My chat program has about 22 so 
 far. But for this tutorial these two will do fine. Now I'm assuming you already 
 know how to connect two computers together using winsock so I'm not going to 
 go into that. If you need help then there are plenty of good examples and tutorials 
 on the basics of winsock on this web site. </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><b>[Making 
 a Fast Send Sub Routine] </b></font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">So 
 we have our data types ready. Now we can code a really cool Sub that can really 
 speed up sending data (coding wise) </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">=================== 
 </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#666666">Public 
 Sub Send_Data(dType As DataTypes, Optional dData As String)<br>
 Dim oData As String <br>
 Dim oType As String <br>
 Dim oAll As String <br>
 <br>
 oType = dType<br>
 If Len(oType) < 2 Then <br>
 oType = "0" & dType<br>
 Else oType = dType <br>
 End If <br>
 <br>
 oData = dData <br>
 oAll = "¬" & oType & oData<br>
 <br>
 If WINSOCKCONTROL.State <> sckConnected <br>
 Then MsgBox "ERROR: Not Connected", vbCritical, "No Connection"<br>
 Exit Sub<br>
 End If <br>
 <br>
 WINSOCKCONTROL.SendData (oAll)<br>
 End Sub <br>
 </font><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><br>
 =================== <br>
 <br>
 Okay basically this is used so that if you want to send a message you can do 
 it with one line of code and do it really fast. It also brings up a really cool 
 menu for choosing the data type. It also makes sure the data type uses 2 characters 
 so if the number for the type is less than 10 then it adds the character "0" 
 to the beginning and then the single digit afterward. Its basically used so 
 that its always 2 characters and can be easily ripped out of the data packet 
 later on.<br>
 <br>
 Okay so you've sent the data. Now you need something to decipher it on the other 
 side. But first I think its time I explained what the "¬" is for. Now when 
 I started playing around with my chat program on the Internet I found that the 
 data was getting merged together. Basically sometimes two data packets merged 
 to look something like this 02Hi04David. When this happened my program went 
 to find the data type "02" then sent the message "hi04david" which was annoying 
 because the 04david was supposed to be a nickname and not a message. So any 
 ways back to the point.<br>
 <br>
 <b>[Splitting merged data packets]</b><br>
 <br>
 I came up with the idea of adding a symbol to the beginning of all the packets 
 then splitting the packets up after every "¬" symbol. It took a while to 
 figure out but I managed it&#8230; so here the code to do it&#8230;. By the way there is 
 a reference to the Incoming_Data Sub, which we will cover afterwards. <br>
 <br>
 =================== <br>
 <font color="#CCFF00"><br>
 <font color="#666666">Public Sub Split_Packet(iData As String) <br>
 Dim sPackS As Integer<br>
 Dim sPackE As Integer<br>
 Dim i As Integer<br>
 Dim j As Integer<br>
 Dim sLast As Integer<br>
 Dim sType As DataTypes<br>
 Dim sData As String<br>
 Dim sAllData As String<br>
 <br>
 For i = 1 To Len(iData) <br>
 <br>
 If Mid(iData, i, 1) = "¬" Then <br>
 sPackS = i + 1 <br>
 <br>
 For j = sPackS To Len(iData)<br>
 <br>
 If (j = Len(iData)) And Mid(iData, j, 1) <> "¬" Then <br>
 <br>
 sPackE = Len(iData) <br>
 sAllData = Mid(iData, sPackS, sPackE) '- (sPackS + 1)))<br>
 <br>
 If Len(sAllData) < 3 Then <br>
 sType = sAllData<br>
 Else <br>
 <br>
 sType = Mid(sAllData, 1, 2) <br>
 sData = Mid(sAllData, 3, (Len(sAllData) - 2))<br>
 <br>
 End If <br>
 Call incoming_data(sType, sData) <br>
 Exit Sub <br>
 <br>
 ElseIf Mid(iData, j, 1) = "¬" Then <br>
 <br>
 sPackE = (j - 2) <br>
 sAllData = Mid(iData, sPackS, (sPackE - sPackS) + 2)<br>
 <br>
 If Len(sAllData) < 3 Then<br>
 sType = sAllData<br>
 Else <br>
 <br>
 sType = Mid(sAllData, 1, 2)<br>
 sData = Mid(sAllData, 3, (Len(sAllData) - 2)) <br>
 End If <br>
 <br>
 Call incoming_data(sType, sData)<br>
 <br>
 Exit For<br>
 <br>
 End If <br>
 <br>
 Next j <br>
 <br>
 End If <br>
 <br>
 Next i <br>
 <br>
 End Sub </font><br>
 </font> </font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000">===================</font></p>
<p><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><font color="#0000FF">The 
 symbol "¬" is used by holding shift and then the button next to 
 the number 1. It can be any symbol you wish, but I chose this symbol becuase 
 I felt that it would not be used by the people testing the program and so I 
 would be safe using it.<br>
 </font></font><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><br>
 Okay all this does it constantly loops around until it's found all the merged 
 packets (if any) then send it to another sub to be processed. <br>
 <br>
 Now if you're actually an expert at Winsock and wonder why I just didn't just 
 use the "send complete" event in Winsock. Well its because it kind of freezes 
 up when u have 30 connections and it gets really slow doing it that way.<br>
 <br>
 <b>[Processing the Incoming Data]</b><br>
 <br>
 Okay we've now sorted the data now we need to do something with it. This is 
 where incoming_data comes in. Basically all we do here is do a select case statement 
 on the incoming data type. Then do something with the data.<br>
 <br>
 ===================<br>
 <br>
 <font color="#666666">Public Sub incoming_data(iType As DataTypes, iData As 
 String) <br>
 <br>
 Select Case iType <br>
 Case DataTypes.MESSAGE <br>
 'send the data or message to the textbox <br>
 txt_dialog.Text = txt_dialog.Text & iData & vbCrLf <br>
 Case DataTypes.NICKNAME <br>
 'set the remote users nickname as the data <br>
 lbl_usernick.caption = idata <br>
 end select </font><br>
 <br>
 =================== <br>
 <br>
 <font color="#0000FF">So you now need to know the steps what you should do on 
 a Data_Arival Event in winsock it is this....<br>
 >ON - DATA_ARRIVAL_WINSOCK><br>
 >SEND THE DATA TO ><br>
 >SPLIT_PACKET ><br>
 >SEND THE PACKETS TO><br>
 >INCOMING_DATA</font></font><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"> 
 ><br>
 <font color="#0000FF">>DO SOMETHING WITH THE DATA AND ITS TYPE. </font><br>
 <br>
 Now I mean this is quite basic what I've shown you here. But you can add new 
 data types and do new things on that type of data. There is no limit to how 
 many you want. Although don't go over 100 type if your using my code&#8230; come to 
 think of it. If you manage to get over 100 individual types email me or post 
 a comment because I don't believe its possible&#8230;. hehe&#8230;. I have multi channels 
 and multi users and I've only got 22 types! Anyway I hope this tutorial has 
 helped you a little. or if ya want to tell me how to do sothing proberly then 
 please tell me becuase I've only recently started on VB<br>
 <br>
 Please leave a comment if you need any help or u would like to thank me or if 
 you want to tell me that I'm wrong or if there is an error in the code. Thanks</font><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><br>
 <br>
 oh btw, I'll be uploading the Simple Chat 2.8 as soon as I comment the code. 
 It uses what I have shown you above and a little more. ;) so watch out for it. 
 I'm also doing something I havent seen on here. so keep ya eye out.<br>
 <br>
 Thanks for reading</font><font face="Verdana, Arial, Helvetica, sans-serif" size="2" color="#000000"><br>
 <br>
 CrAKiN-ShOt <br>
 <a href="mailto:crakinshot@hotmail.com">crakinshot@hotmail.com </a></font></p>