[Zigon]

I've been missunderstood...

Quote

Otherwise we're not going to help you eavesdrop on commercial software so you can gather credit card details.

It is nothing like that!
All payements are made by cash only, so there is no need for credit card details. All we want is to pull a draw (something like bingo or something - I do not know how it is called in English) and all I need is the "bill number" (that is the number of the transaction on the bill, the customer recieves when the payement is made) and the amount on that bill.
I can do that by entering those numbers by hand, but that wound be time consuming when ringing bills and all I wanted is to automate the whole thing. As for today, we're doing it "by hand", so we print the copy of the bill, the customer signs it and the at the end of the period, we calculate the sums and worked out which one was the best customer, so we could give-out the gift...
I am sorry as English is not my native language and it's been a while since I wrote or try to explain soething in English...

Now I do hope you understand what I mean and what I am trying to acchieve. There are absolutely no bad intentions there as there is no need to collect ANY of the vital customer info (we really do not need it anyway). We're just tryin to track how the bussiness is going and reward the best buyers (I hope I wrote that right).

Regards and best wishes!

This post has been edited by tlhIn`toq: 21 March 2012 - 05:27 AM
Reason for edit:: tag fix

[Robin19]

Quote

All we want is to pull a draw (something like bingo or something - I do not know how it is called in English)

Raffle or lottery would probably be the American English word you are looking for.

It still stands that you are eavesdropping on commercial software. If there is a SQL database already being used by the software, I would find a way to query that data than try to replicate parts of that data in another space. Or find out if the software you are using can somehow give you a report that you can use. At work, we have one piece of software that records the data in a proprietary format. We want to run a report off of it, which would be easy with SQL Reporting Services. Instead, we "export" the data into a CSV and use Crystal Reports to read the data. It wouldn't be that hard to use C# to read the CSV and do what you want to do.

[Zigon]

Thanks for the reply!

Actually I was thinking about (also tried it) redirecting the printer to the text file and then red the lines, but there's a problem printing into the file and to the printer at the same time.

About querying the database, I had a problem opening it, because the system wouldn't allow me to do so (err.: the file is allready in use). My guess would be it's being used (locked) by SQL server. That's because even if I close down the application, I still cannot access the database.

Therefore I was thinking about reading the printer output directly, catching the escape sequences for the new line, so I could count the lines.

All I am interested in is the bill number (I hope it called that) and the amount on that bill. I would then save that data along with the customer ID (or name) to my database. At the end of the period, I would pull that data out and pay out the present.

The easiest way for me would be to connect to the DB (I have established the connection) but I can't open it, to read the data.

Now, I hoe you understand, what I mean...

Regards and best wishes!

[Zigon]

Can't find the "Edit" button, so...

Another problem is, that I need to do this "on the fly" - for every transaction being made by the clerk.

[tlhIn`toq]

I think Robin had the better answer: Just ask the database what receipt (docket) numbers have been issued.

IF you aren't notifying people they are winners in real time at the checkout stand you could also (programmatically) query the database for the start and end receipt numbers for that day and select one at random. Then post a sign saying "Tuesday's winner: Docket 123465" It brings people back if only to check their numbers, and returning customers mean more sales.

[Zigon]

Quote

you could also (programmatically) query the database

well, this is the problem! It just won't let me!
When I try to open the database, I get the error saying that the file is allready in use.

I've tried closing the main application, but to no avail. The error was still there... hence my question about reading the printer output.

Maybe I'm doing it all wrong. I don't know. But this seemed to be the easiest solution at the time.

If only I could open the database (just for reading) that would solve the problem.

I was thinking also about enumerating the main window of the application with some native API calls (FindWindow, FindWindowEx) catching the text with SendMessage with WM_GETTEXT. But I believe this would be too much hassle and also it would resolve only part of my problem as the "docket" number is not displayed.

Any suggestions?

Regards and best wishes!

[eclipsed4utoo]

Zigon, on 21 March 2012 - 01:26 AM, said:

When I try to open the database, I get the error saying that the file is allready in use.

How are you trying to opening it?

[tlhIn`toq]

What "file"? What is the type of database being used for this?

Database tutorials:

See FAQ # 21. (Click the SHOW button below)


TOP most asked:
What does this error message mean?
FAQ 2: How do I debug
FAQ 3: How do I make Class1/Form1 talk to Class2/Form2


FAQ (Frequently Asked Questions - Updated Mar 2012

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My program is broken:


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  We see this a LOT, especially with rookies using textbox for numeric input.
  
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  There are a LOT of articles on making a NumericTextBox. Try googling "C# NumericTextBox" and you should find a lot, such as this one on the MSDN:
  
  http://msdn.microsof...4(v=vs.80).aspx
  
  Once you study the code you'll see that as each key is pressed it is checked to see if it is a number. If not, then it is ignored. Thus the user can only enter numerically valid values.
  
  
  
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  Spoiler

  A: Make your new project a WinForms project. Then go back to project properties (Right-click on the project, select Properties).
  
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• Q:I'm trying to teach myself programming. I'm writing a program to do xyz, rather than following a guided self teaching book or lesson plan or on-line tutorial because I just don't learn from books.
  A:
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  I'm sorry for how this sounds. I tend to take the stance that I can do you more good and give you more long-term meaningful help by being frank and give you adult-level honesty. I don't feel it does anyone any good to coddle them and do nothing but blow sunshine and rainbows up their skirt. I'd rather say something to motivate you than feel my place is to bolster your false high self esteem.
  
  

  Quote

  ]
  I've tried going through those, the only way im learning is through struggling to write code from scratch, the thought process i guess is helping me, i've tried reading sooo much and watching videos but honestly im not learning until i actaully type it.

  
  
  I hear this a lot and the only thing I can think is students are buying the wrong books. Or they read the information and don't feel they need to actually work the lessons/exercises. This argument sounds like there are only two choices:
  

  • Develop from scratch even though they haven't learned the language yet.
    
  • Just read C# dictionaries.

  
  
  Maybe this is from students buying the course textbook and reading it on their own, without the benefit of the teacher and their lesson plan and exercise assignments. When one mis-uses the materials, or only has 25% of the materials, of course they won't learn.
  
  Here's a tip when selecting a book: If it is a dictionary of the language it is not a teaching book. Titles like "C# 4.0, The Complete Language" are not teaching books. If the title includes the words "Learn" or "Master" or "Teach" they might be teaching books. "Learn C# in 21 days", "Master C# in 2 hours a night", "Head First C#, A self-teaching guide" Then they are probably teaching books with a lesson plan and exercises to help you build up skills.
  
  Obviously you didn't read the resources list I posted or get any one of the NUMEROUS self-teaching books.
  
  Self-teaching books HAVE YOU TYPING CODE. They are NOT just reading as you describe.
  
  C# is a language just like Russian or English. You cannot learn Italian by just reading an Italian dictionary. Or even reading an English-to-Italian dictionary. You have to take lessons and do the learning exercises. Those lessons and exercises are developed by professionals to take place in a sequence proven to work, by taking the student from simple to complex concepts. You did not learn how to compose literary works in English by just reading a dictionary. You worked at lessons that taught you the syntactical use of verbs, nouns, additives and so on. You worked lessons that had you build simple things first like "Those are my apples. These are your pencils", and worked up from there.
  
  So why are you trying to "just read" to learn C#? Or why are you insisting on trying to design and code a working program without first learning the language? It makes no sense! Its like saying you have to design and write a mystery novel as your introductory educational process to learn German. Its just a fraking ridiculous argument to try to take or defend.
  
  There are numerous on-line learning series on the internet that have you learning and WRITING code, not just reading. We have them right here on DIC and they have been linked to you several times. There are many good guided self-teaching books, that once again are NOT just reading but teaching through proven methods of:
  

  • Introduce new material
    
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  Yet you insist that you don't need to go the route that has worked for the 3 generation of coders before you: Representatives of which are here TELLING you that is the way to learn this science/skill/art.
  
  

  Quote

  would i be able to take out the private double[] months = new double[12];
  and place it in a method instead of leaving it in a private field, why does it have to be in a private field as opposed to a method in just placing it in the main method?

  
  
  Questions like this last one show just how badly you need to stop trying to write this program and just concentrate on learning the language through some sort of guided lesson plan. This question is filled with so much lack of understanding that it is hard to know where to start in an effort to answer it. To answer this someone would have to back up 5 chapters and help you get a grasp of certain introductory concepts. It's not right to ask that of people that have already devoted tens or hundreds of hours to develop the tutorials we have here. You shouldn't be asking them to repeat themselves because you feel you need special hand-holding or because you don't want to get the right books or because you don't want to actually work the exercises in the books or tutorials.
  
  
  
  
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• Q: I am doing a dice game for a school homework and...
  A:Drawing dice on the console
  
  
  
  
• Q:

  Quote

  Hi,I'm currently learning C# in class at the moment and I'm a little bit stuck on what this question means.[...]show me where I can get help,
  
  A:
  Spoiler

  Your professor. That's where to start for a couple reasons:
  1. They are getting paid to teach you. If they aren't teaching you this needs to come to their attention and that of their superiors.
  2. You're the one paying them. Tens of thousands of dollars for your education. You need to learn to take every ounce of knowledge you can from these teachers and not sit passively back and try to learn it on the outside. If you were going to do that then you didn't need to take out all the student loans that are going to keep you in debt for the next 15 years.
  3. You need to let the teacher do their job. If you are struggling here you don't want to hide it. You need them to be aware of position so they can give you the time and attention you need. Otherwise you will be a little lost on chapter 1. A little more on 2. Way behind by chapter 3. You have to get a good foundation now if you are to gain anything in the later lessons.
  
  
  
• Q: I want to write a program that does x, y and z with features for A, B, and C. {Notice there is no question in this question}
  A:
  Spoiler

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  A:
  Spoiler

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  Read this article!!!!!
  
  
  
  Discussion topics:
  
  
• Q: What is the best programming language/OS? What programming language/OS should I learn?
  A:
  Spoiler

  All of them. And none of them. You might as well be asking "What is the best kind of vehicle?" Because the answer for both questions is "It depends on your needs and what personally suites you the best." C, C++, C#, Objective-C, Cocoa, F#, Visual Basic, Python, JAVA...
  
  Are all good languages. They all have their pros and cons. They each have their strengths and weaknesses. Some have stronger footholds in some markets than others. Do you want to write for iPhone/iPad then you need Objective-C. Do you want to write for generic mobile phone use then you need JAVA. And so on. If you have no idea what area of programming you want to move to (Gaming, Financial, Windows, Macintosh, Cell phones) then nobody can advise you on a language. Personally, I would point you to C# because, like it or not, Microsoft owns the desktop computer market and C# will teach you good habits of design, OOP (Object Oriented Programming) design, inheritance and so on: Concepts that translate well to all other OOP languages.
  
  The OS is a by-product of the type of coding you want to do, which in turn dictates the language you need, which then decides the operating system you probably need. Not the other way around.
  
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  helicopters? XBox games requires the .NET XNA framework so you are now in Windows. Do you want to do embedded controls for automotive computers? Do you just love MS Office and love to make extensions for it? Do you want to work on web apps or desktop apps or mobile apps?
  
  Do you now see why we can't even begin to tell you what is best for you? Only you know what you like and what you don't like. Only you know what area of programming is interesting to you. If you ask me for advice I might tell you video processing for the movie industry is great so you should get a Mac. Someone else is going to tell you cool stories of working on CSI lab equipment so you should do C embedded stuff.
  
  The short answer for this question is: Get in touch with your own wants and needs then think for yourself.
  
  Join this heated discussion on the topic:
  http://www.dreaminco...anguage-to-use/
  
  VB6 is dead
  
  
• Q: How do I become a programmer?
  A: Click the link
  
  
  
• Q: I'm not really sure what I want to do with my future? Do you guys like programming? I think I kinda like math and games and computers? What should I do or study?
  A:
  Spoiler

  
  You are asking a very vague, generalize question about a broad topic.
  You might as well be asking... What is the best kind of vehicle to buy? Or what is the best kind of plastic to make? It all depends on your needs... Your area of business.
  
  If you are interested in embedded devices like computers that control automobile engines it is still programming - but it is entirely different to writing a point of sale program meant to be used as a self-service kiosk like you see at Home Depot. And that is entirely different to writing a program that is meant to be used on a mobile platform.
  
  You need to make a decision about what kind of programming, what area of interest, what industry you want to work in, before you can worry about the specifics of which language and OS and platform.
  Which Language Should I Learn?
  DIC Tutorials Section
  Good thread on the topic
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• Q: What's your installation like? What sofware do you use? What are your Visual Studio extensions?
  A:
  Spoiler

  
  

  • Host Operating System - 16gig, quadcore, 3x24" Dell LCDs at 1920x1200 (2 landscape, 1 portrait)
    
    • 20 times of on-line update/reboot cycle
      
    • Device Drivers
    • AVG antivirus
      
    • VMware workstation
    
    
    • VM Operating System
      
      • 20 times of on-line update/reboot cycle
        
      • Device Drivers
        
      • Visual Studio
        
        • ReSharper
          
        • Dotfuscator
          
        • nArrange
          
        • XAML regions
          
        • XAML code cleanup
          
        • InstallShield
        
        
      • Expression blend studio
        
      • MS Office
        
      • SnagIt
        
      • Safari
        
      • iTunes
        
      • Fences
        
      • Yahoo messenger
        
      • FoxIt PDF reader
        
      • AnyDVD (I have DVDs from 3 different regions)
        
      • TightVNC
        
      • Dropbox
        
      • AVG anti-virus
        
      • Quicken
        
      • Canon RAW codec
        
      • Shark007 codec pack for Media Center
        
      • Another 20 rounds of on-line update/reboot
        
      • Take a snapshot of the VM machine for easy restoration

  
  
  That is my entire install
  
  
  
  
  
  
  
  
  Working for myself/Deploying/Selling software:
  
  
• Q:How do I stay a free lance coder for a living?
  A:http://justcreatived...eelancing-life/
  
  
• Q: How do I become a better coder?
  Read this, and practice a lot.
  How to be a better coder
  
  
• Q: Are there any resources for small C# projects a novice to become a better coder?
  A:
  Spoiler

  There is a novice projects thread here on DIC. But here's my advice whenever this comes up:
  
  Look around. Anyone who can't find a dozen projects a day by just walking through life, is doing so with their eyes closed to the world.
  

  • Do you like the weather? What about a program to get the various weather reports from different web sites? Or to integrate with one of the numerous USB weather station hobby kits on the market?
    
  • Do you like the run? What about a program to log your runs, routes and progress?
    
  • Do you like movies? What about a program to catalog all your DVD's and AVI's?
    
  • Do you like photography? What about a program to browse your images, assign tags and GPS?
    
  • Do you like shooting? What about a program to track your aim and improvement?
    
  • What about every time you walk into a business and someone says "Oh, I'm sorry. The computers are slow/suck. This is going to take 10 minutes and 25 screens." Sounds like an opportunity to make and maybe even sell them a new program. So go home and make it first before you open your mouth. If you succeed in something great. If you fail, then you know where to study more and you haven't embarrassed yourself.

  
  
  What about every time you walk into a business and someone says "Oh, I'm sorry. The computers are slow/suck. This is going to take 10 minutes and 25 screens." Sounds like an opportunity to make and maybe even sell them a new program. So go home and make it first before you open your mouth.
  
  If you succeed in something great. If you fail, then you know where to study more and you haven't embarrassed yourself.
  
  Go to any of the on-line coder for hire sites. Read the new contract descriptions. DON'T BID ON THEM. Just read them. This will tell you what is requested by employers so you know where you have the potential to make money, and tell you where you should study. Then pick a project and build it. TRACK YOUR TIME. If you don't know how long it takes you to build a project then you won't be able to bid on contracts. If you bid $50 for 50 hours of work you're going to starve to death. Again, building projects just to learn the technology and learn your own speed and weaknesses is something we all do/did and you need to do too. Once you can build a project just for the learning experience, fast enough that you could have made a competitive bid... Now you can start considering actually bidding on new contracts that are in your skill set.
  
  
  
  
• Q: How do I sell the software I've developed?
  A:http://www.dreaminco...m_notifications
  
  
• Q: How do I decide how much to charge for my application?
  A: Read this
  
  
• Q: How do I deploy my program / Make an installer?
  A: C# application deployment project
  Include the smallest .NET possible

---

[Zigon]

Actually it happens when I point to it with the OpenFile dialog

		private void btnOpenFile_Click(object sender, EventArgs e)
			{
			OpenFileDialog ofd = new OpenFileDialog();
			ofd.ShowDialog();
			//if ofd.FileOk
			filePath = ofd.FileName;

			}

I then include the filePath string into my Connectionstring. Like this:

            con = new System.Data.SqlClient.SqlConnection();
            ds1 = new DataSet();
            string sql = "SELECT * FROM POSRacuni";
			FindFile();
            con.ConnectionString="Data Source=.\\SQLEXPRESS;AttachDbFilename=" + filePath + ";Integrated Security=True;Connect Timeout=30;User Instance=True";

but it never gets there. It stops right on clicking the OPEN button on the OpenFileDialog.


The database is "XXXXXX.mdf" so I guess it's an SQL database. I know it contains several tabels (I can see them in backup of the database itself) and I know field names, but the backup is done every seven days or so that data is not relevant.

Regards and best wishes!

[tlhIn`toq]

Quote

It stops right on clicking the OPEN button on the OpenFileDialog.

Do you know how to place breakpoints and understand about debugging?
You shouldn't be guessing which line of code its stopping on.

I'm suspicious of the FindFile() method call in the second code block. What is the purpose of having that wedged in the middle of your database communication stuff?

Placing breakpoints and walking through the code line by line allows you to actually WATCH it execute. Visualizing what your code does will let you see why it behaves the way it does.

It would be well worth your time to do the tutorials on FAQ 2. A couple hours learning this skill will save you hundreds of hours of confusion in one project alone.


See FAQ # 2. (Click the SHOW button below)


TOP most asked:
What does this error message mean?
FAQ 2: How do I debug
FAQ 3: How do I make Class1/Form1 talk to Class2/Form2


FAQ (Frequently Asked Questions - Updated Mar 2012

Spoiler

My program is broken:


• Q: My program doesn't work. I didn't show you any code or actually tell you the error message. How do I fix it?
  
  Spoiler

  A: What have you tried so far? It is a requirment of this site that you at least make an effort to research (read the MSDN) and code a good faith effort for your own problem. Can you share your current code with us and better explain what issues or errors you are getting? Give us something to go on
  
  
  
  
• Q: I do x and y happens which I didn't expect but I don't know how to figure out why. How do I debug and find my problem?
  A:
  Spoiler

  • Debugging video 1: Breakpoints and Local variables
    
  • Debugging video 2: Advanced breakpoints
    
  • Debugging tutorial
    
  • Debugging tips
    
  • Debugging in detail
    
  • Great debugging tips
    
  • It still doesn't work, article
    
  • Debugging tools survival guide
    
  • Video: Tips & Tricks to use Visual Studio to the fullest
  
  
  
  
  
  How do I?
  
  
• Q: ...get Form 'A' to make a change or talk to Form 'B'
  
  Spoiler

  A:

  • See this thread for the simplest of example code between two forms.
    
    The tutorials below actually teach and explain it further.
    
  • Passing values between forms/classes
    
  • Bulding an application - Part 1
    
  • Building an application - Part 2
    
  • Quick and easy custom events
  
  
• Delegates, Lambdas and Events
  
  
  
• Q: ...make a password/login form?
  A: Password handling tutorial
  
  
• Q: ... browse for/open a file?
  Read this tutorial
  
  
• Q: ...make a chat or client-server application?
  A:Client/server chat tutorial
  Peer-to-peer chat
  
  
• Q: ... get my program to programmatically simulate a mouse click or button press?
  A: Simulate mouse and keystroke (even to another application)
  
  
• Q: ... save data, save properties, save environmental variables, serialize my data/class?
  A:
  Spoiler

  • Separating data from GUI - PLUS - serializing the data to XML
    
  • Working with environmental variables
    
  • Writing a text file tutorial.
    
  • Reading a text file tutorial.
  
  
  
• Q:... get sound in my program?
  A: Adding sound to your C# application
  
  
• Q: ... use the serial port?
  A: Serial port communication
  
  
• Q: ...do compression or .zip files?
  A:
  • (de)Compression tutorial
    
  • Zip files tutorial
  
  
  
• Q:...do multi-threading? Having a problem with cross-threading...
  
  Spoiler

  A:

  • Cross thread calls tutorial
    
  • How to use a thread pool.
    
  • Decouple your multi-threaded work from the GUI so forms don't hang
    
  • thread synchonization
    
  • Advanced threading
    
  • MSDN asynch communication
  
  
  
• Q: ... make my textbox offer suggestions as the user types. (Autocomplete)
  A: Creating an auto-complete textbox
  
  
• Q: ... make a textbox just accept numbers and not letters?
  A: Read this thread
  
• Q:I get an error when I try to use a textbox for numeric values and the user types non-numbers. What do I do?
  A:
  Spoiler

  We see this a LOT, especially with rookies using textbox for numeric input.
  
  Any input that can't be converted to a number will do this.
  "5" can become 5
  "yogi" cannot become a number
  string.empty cannot become a number
  
  You would be best off changing from a textbox to a NumericUpDown or to inherit from textbox to make a numerictextbox.
  
  There are a LOT of articles on making a NumericTextBox. Try googling "C# NumericTextBox" and you should find a lot, such as this one on the MSDN:
  
  http://msdn.microsof...4(v=vs.80).aspx
  
  Once you study the code you'll see that as each key is pressed it is checked to see if it is a number. If not, then it is ignored. Thus the user can only enter numerically valid values.
  
  
  
• Q: ... use PInvoke and the Win32 api calls to get functions not available in .NET framework?
  A: Using the Win32 API Tutorial
  
  
• Q: ... have both a WinForms Windows app, and still have a Console window open?
  
  Spoiler

  A: Make your new project a WinForms project. Then go back to project properties (Right-click on the project, select Properties).
  
  On the Application tab go to the dropdown that says "Windows Forms" and change it to "Console Application." You now have a WinForms application with a console window. I do this on occassion to see my Console.WriteLine statements when I am debugging. But don't consider this mixed mode operation a proper way to release an application for real-world use.
  
  
  
• Q: ... make a username/password logon (login) system?
  A: Read this tutorial
  
  
  
  
  
  Can someone explain...
  
  
• Q: ... how to do x, y, z with the HTML that comes out of a website ...
  A: Check out the HTML Agility Pack. Yes its free.
  
  
• Q:... how to do x,y,z with a database {probably for the first time}...
  A: Read this tutorial
  Entire section of tutorials
  Parameterizing Your SQL Queries: The RIGHT Way To Query A Database.
  
  
• Q: Can someone explain bitwise operations?
  A: Terrific explanation by CodingSup3rnatur@l-360. Be sure to +1 him for this thread.
  
  
  
  
  
  
  I'm lost while learning xyz... I don't know where to begin...
  
  
  
• Q:I'm trying to teach myself programming. I'm writing a program to do xyz, rather than following a guided self teaching book or lesson plan or on-line tutorial because I just don't learn from books.
  A:
  Spoiler

  I'm sorry for how this sounds. I tend to take the stance that I can do you more good and give you more long-term meaningful help by being frank and give you adult-level honesty. I don't feel it does anyone any good to coddle them and do nothing but blow sunshine and rainbows up their skirt. I'd rather say something to motivate you than feel my place is to bolster your false high self esteem.
  
  

  Quote

  ]
  I've tried going through those, the only way im learning is through struggling to write code from scratch, the thought process i guess is helping me, i've tried reading sooo much and watching videos but honestly im not learning until i actaully type it.

  
  
  I hear this a lot and the only thing I can think is students are buying the wrong books. Or they read the information and don't feel they need to actually work the lessons/exercises. This argument sounds like there are only two choices:
  

  • Develop from scratch even though they haven't learned the language yet.
    
  • Just read C# dictionaries.

  
  
  Maybe this is from students buying the course textbook and reading it on their own, without the benefit of the teacher and their lesson plan and exercise assignments. When one mis-uses the materials, or only has 25% of the materials, of course they won't learn.
  
  Here's a tip when selecting a book: If it is a dictionary of the language it is not a teaching book. Titles like "C# 4.0, The Complete Language" are not teaching books. If the title includes the words "Learn" or "Master" or "Teach" they might be teaching books. "Learn C# in 21 days", "Master C# in 2 hours a night", "Head First C#, A self-teaching guide" Then they are probably teaching books with a lesson plan and exercises to help you build up skills.
  
  Obviously you didn't read the resources list I posted or get any one of the NUMEROUS self-teaching books.
  
  Self-teaching books HAVE YOU TYPING CODE. They are NOT just reading as you describe.
  
  C# is a language just like Russian or English. You cannot learn Italian by just reading an Italian dictionary. Or even reading an English-to-Italian dictionary. You have to take lessons and do the learning exercises. Those lessons and exercises are developed by professionals to take place in a sequence proven to work, by taking the student from simple to complex concepts. You did not learn how to compose literary works in English by just reading a dictionary. You worked at lessons that taught you the syntactical use of verbs, nouns, additives and so on. You worked lessons that had you build simple things first like "Those are my apples. These are your pencils", and worked up from there.
  
  So why are you trying to "just read" to learn C#? Or why are you insisting on trying to design and code a working program without first learning the language? It makes no sense! Its like saying you have to design and write a mystery novel as your introductory educational process to learn German. Its just a fraking ridiculous argument to try to take or defend.
  
  There are numerous on-line learning series on the internet that have you learning and WRITING code, not just reading. We have them right here on DIC and they have been linked to you several times. There are many good guided self-teaching books, that once again are NOT just reading but teaching through proven methods of:
  

  • Introduce new material
    
  • Have student exercise with new material

  
  
  Yet you insist that you don't need to go the route that has worked for the 3 generation of coders before you: Representatives of which are here TELLING you that is the way to learn this science/skill/art.
  
  

  Quote

  would i be able to take out the private double[] months = new double[12];
  and place it in a method instead of leaving it in a private field, why does it have to be in a private field as opposed to a method in just placing it in the main method?

  
  
  Questions like this last one show just how badly you need to stop trying to write this program and just concentrate on learning the language through some sort of guided lesson plan. This question is filled with so much lack of understanding that it is hard to know where to start in an effort to answer it. To answer this someone would have to back up 5 chapters and help you get a grasp of certain introductory concepts. It's not right to ask that of people that have already devoted tens or hundreds of hours to develop the tutorials we have here. You shouldn't be asking them to repeat themselves because you feel you need special hand-holding or because you don't want to get the right books or because you don't want to actually work the exercises in the books or tutorials.
  
  
  
  
• Q: I am making a calculator as my school homework project and ...
  A: Calculator tutorial
  
  
• Q: I've been struggling with this for days/weeks and I can't figure it out and my professor is worthless and can't teach. Can someone here explain it to me?
  A:
  Spoiler

  If you are struggling with how to do this you need to talk to your professor. Let him/her know you are struggling at this early stage in class. Make your professor do the job (s)he gets paid to do by either helping you or finding you a tutor or giving you more exercises from earlier in the book. You are paying for this education. Be an active part in not allowing the teacher to brush you off and let you slip through the cracks. If the other 50 people in class aren't struggling then don't blame the teacher. If the other 50 people are struggling then you all need to go to the professor's superior and tell him/her. If the prof is really incompetent then you don't need to help him keep his cushy 100,000/year job. If the prof isn't incompetent then you need to study harder or consider buying another book on programming. You aren't required to ONLY use the text book provided for the class.
  "How do you resolve your issues" survey.
  
  
  
  
• Q: I am doing a dice game for a school homework and...
  A:Drawing dice on the console
  
  
  
  
• Q:

  Quote

  Hi,I'm currently learning C# in class at the moment and I'm a little bit stuck on what this question means.[...]show me where I can get help,
  
  A:
  Spoiler

  Your professor. That's where to start for a couple reasons:
  1. They are getting paid to teach you. If they aren't teaching you this needs to come to their attention and that of their superiors.
  2. You're the one paying them. Tens of thousands of dollars for your education. You need to learn to take every ounce of knowledge you can from these teachers and not sit passively back and try to learn it on the outside. If you were going to do that then you didn't need to take out all the student loans that are going to keep you in debt for the next 15 years.
  3. You need to let the teacher do their job. If you are struggling here you don't want to hide it. You need them to be aware of position so they can give you the time and attention you need. Otherwise you will be a little lost on chapter 1. A little more on 2. Way behind by chapter 3. You have to get a good foundation now if you are to gain anything in the later lessons.
  
  
  
• Q: I want to write a program that does x, y and z with features for A, B, and C. {Notice there is no question in this question}
  A:
  Spoiler

  That is a very good statement of intent. Go right ahead. You don't need to announce your intentions to us, nor get anyone's permission. After you have made an effort to your own code (in good faith as described in the Welcome DIC email you got when you joined) and the forum rules that I'm sure you read before posting, and you have a QUESTION about this project... Please post the QUESTION here in this same thread. There is no need to start a new thread for this same topic.
  
  
  
• Q: I need to code to do x... Someone tell me the code for y...
  A:
  Spoiler

  Your question is about to get bounced for begging for code anyway but...
  So you're asking the volunteers here to write your code for you, to make it do everything in your wish list?
  
  Please read the rules. You seem to misunderstand what we do here. We help people learn to code. We help people with their projects. We help people better understand the errors and exceptions they are getting so they can fix their issues. We are not a free code writing service. If you have made an effort to code a specific feature, but are not getting the results you wanted then please post the relivant code for that feature along with the error messages or an explanation of what results you are seeing as compared to the results you were expecting, and we will try to guide you onto the right path.
  Read this article!!!!!
  
  
  
  Discussion topics:
  
  
• Q: What is the best programming language/OS? What programming language/OS should I learn?
  A:
  Spoiler

  All of them. And none of them. You might as well be asking "What is the best kind of vehicle?" Because the answer for both questions is "It depends on your needs and what personally suites you the best." C, C++, C#, Objective-C, Cocoa, F#, Visual Basic, Python, JAVA...
  
  Are all good languages. They all have their pros and cons. They each have their strengths and weaknesses. Some have stronger footholds in some markets than others. Do you want to write for iPhone/iPad then you need Objective-C. Do you want to write for generic mobile phone use then you need JAVA. And so on. If you have no idea what area of programming you want to move to (Gaming, Financial, Windows, Macintosh, Cell phones) then nobody can advise you on a language. Personally, I would point you to C# because, like it or not, Microsoft owns the desktop computer market and C# will teach you good habits of design, OOP (Object Oriented Programming) design, inheritance and so on: Concepts that translate well to all other OOP languages.
  
  The OS is a by-product of the type of coding you want to do, which in turn dictates the language you need, which then decides the operating system you probably need. Not the other way around.
  
  Do you want to code apps for iOS devices like the iPad and iPhone? Then you need a Macintosh to do it right. Are you hankering to do machine vision programming? Industrial robot control? Financial applications?
  
  What are your programming goals? Do you want to market $9.99 desktop applications to the masses? Do you want to make control systems for
  
  helicopters? XBox games requires the .NET XNA framework so you are now in Windows. Do you want to do embedded controls for automotive computers? Do you just love MS Office and love to make extensions for it? Do you want to work on web apps or desktop apps or mobile apps?
  
  Do you now see why we can't even begin to tell you what is best for you? Only you know what you like and what you don't like. Only you know what area of programming is interesting to you. If you ask me for advice I might tell you video processing for the movie industry is great so you should get a Mac. Someone else is going to tell you cool stories of working on CSI lab equipment so you should do C embedded stuff.
  
  The short answer for this question is: Get in touch with your own wants and needs then think for yourself.
  
  Join this heated discussion on the topic:
  http://www.dreaminco...anguage-to-use/
  
  VB6 is dead
  
  
• Q: How do I become a programmer?
  A: Click the link
  
  
  
• Q: I'm not really sure what I want to do with my future? Do you guys like programming? I think I kinda like math and games and computers? What should I do or study?
  A:
  Spoiler

  
  You are asking a very vague, generalize question about a broad topic.
  You might as well be asking... What is the best kind of vehicle to buy? Or what is the best kind of plastic to make? It all depends on your needs... Your area of business.
  
  If you are interested in embedded devices like computers that control automobile engines it is still programming - but it is entirely different to writing a point of sale program meant to be used as a self-service kiosk like you see at Home Depot. And that is entirely different to writing a program that is meant to be used on a mobile platform.
  
  You need to make a decision about what kind of programming, what area of interest, what industry you want to work in, before you can worry about the specifics of which language and OS and platform.
  Which Language Should I Learn?
  DIC Tutorials Section
  Good thread on the topic
  Get experience while you find yourself
  
  
  
• Q: What's your installation like? What sofware do you use? What are your Visual Studio extensions?
  A:
  Spoiler

  
  

  • Host Operating System - 16gig, quadcore, 3x24" Dell LCDs at 1920x1200 (2 landscape, 1 portrait)
    
    • 20 times of on-line update/reboot cycle
      
    • Device Drivers
    • AVG antivirus
      
    • VMware workstation
    
    
    • VM Operating System
      
      • 20 times of on-line update/reboot cycle
        
      • Device Drivers
        
      • Visual Studio
        
        • ReSharper
          
        • Dotfuscator
          
        • nArrange
          
        • XAML regions
          
        • XAML code cleanup
          
        • InstallShield
        
        
      • Expression blend studio
        
      • MS Office
        
      • SnagIt
        
      • Safari
        
      • iTunes
        
      • Fences
        
      • Yahoo messenger
        
      • FoxIt PDF reader
        
      • AnyDVD (I have DVDs from 3 different regions)
        
      • TightVNC
        
      • Dropbox
        
      • AVG anti-virus
        
      • Quicken
        
      • Canon RAW codec
        
      • Shark007 codec pack for Media Center
        
      • Another 20 rounds of on-line update/reboot
        
      • Take a snapshot of the VM machine for easy restoration

  
  
  That is my entire install
  
  
  
  
  
  
  
  
  Working for myself/Deploying/Selling software:
  
  
• Q:How do I stay a free lance coder for a living?
  A:http://justcreatived...eelancing-life/
  
  
• Q: How do I become a better coder?
  Read this, and practice a lot.
  How to be a better coder
  
  
• Q: Are there any resources for small C# projects a novice to become a better coder?
  A:
  Spoiler

  There is a novice projects thread here on DIC. But here's my advice whenever this comes up:
  
  Look around. Anyone who can't find a dozen projects a day by just walking through life, is doing so with their eyes closed to the world.
  

  • Do you like the weather? What about a program to get the various weather reports from different web sites? Or to integrate with one of the numerous USB weather station hobby kits on the market?
    
  • Do you like the run? What about a program to log your runs, routes and progress?
    
  • Do you like movies? What about a program to catalog all your DVD's and AVI's?
    
  • Do you like photography? What about a program to browse your images, assign tags and GPS?
    
  • Do you like shooting? What about a program to track your aim and improvement?
    
  • What about every time you walk into a business and someone says "Oh, I'm sorry. The computers are slow/suck. This is going to take 10 minutes and 25 screens." Sounds like an opportunity to make and maybe even sell them a new program. So go home and make it first before you open your mouth. If you succeed in something great. If you fail, then you know where to study more and you haven't embarrassed yourself.

  
  
  What about every time you walk into a business and someone says "Oh, I'm sorry. The computers are slow/suck. This is going to take 10 minutes and 25 screens." Sounds like an opportunity to make and maybe even sell them a new program. So go home and make it first before you open your mouth.
  
  If you succeed in something great. If you fail, then you know where to study more and you haven't embarrassed yourself.
  
  Go to any of the on-line coder for hire sites. Read the new contract descriptions. DON'T BID ON THEM. Just read them. This will tell you what is requested by employers so you know where you have the potential to make money, and tell you where you should study. Then pick a project and build it. TRACK YOUR TIME. If you don't know how long it takes you to build a project then you won't be able to bid on contracts. If you bid $50 for 50 hours of work you're going to starve to death. Again, building projects just to learn the technology and learn your own speed and weaknesses is something we all do/did and you need to do too. Once you can build a project just for the learning experience, fast enough that you could have made a competitive bid... Now you can start considering actually bidding on new contracts that are in your skill set.
  
  
  
  
• Q: How do I sell the software I've developed?
  A:http://www.dreaminco...m_notifications
  
  
• Q: How do I decide how much to charge for my application?
  A: Read this
  
  
• Q: How do I deploy my program / Make an installer?
  A: C# application deployment project
  Include the smallest .NET possible

---

[eclipsed4utoo]

Check the Services on the PC to see if the SQLEXPRESS service is running. If so, don't try to open the database file. It's already in-use by the database service. Simply connect to the SQLEXPRESS instance WITHOUT attaching the file.

[Zigon]

Thanks guys! I finally got it!
The catch was in thins sentence:

Quote

Simply connect to the SQLEXPRESS instance WITHOUT attaching the file.

I just cannot get used to deal with SQL databases (all I ever worked with was Access DB behind ADO with VB6)

Now it works like a charm!

Now I just have to figure out how to check if there was a record added to the database to trigger my application... I guess I could do it on some interval with a timer and check if the ROWCOUNT has changed...

Again, Thanks a lot!

Regards and best wishes!

[eclipsed4utoo]

You should look into using the SqlDependency class to do this. I wrote a tutorial on how to use it.

http://www.dreaminco...tabase-changes/

It allows you to effectively monitor the database and the database will let you know when the records change. You give it a specific query, and if anything in that query changes, the database notifies the application and you handle it.

[Zigon]

Brilliat! Thanks again!

I'll give it a go.

Thanks and best wishes!