[RobinGoodfellow]

I am writing a small program which will calculate the total number of Hash Tags from a text file. Once the text file has been loaded into my program I try to calculate the total number of times the # symbol appears using the following code which generates an error message;

foreach(char # in text)

I can use the foreach statement to calculate the number of S's or A's in the text but but not the number of #'s. Is this because the # symbol is not recognized as a Char Type by C#? Any help would be greatly appreciated, thank you!

[Gavisann]

You can not name a variable '#'. Name the variable something else like 'pound' and your program should work fine.

example

static void Main()
        {
            string text = "my phone # is";
            foreach (char c in text)
            {
                Console.WriteLine(c);
            }
            Console.Read();
        }

[tlhIn`toq]

It looks a lot like you missunderstand how that line of code works.

Quote

I can use the foreach statement to calculate the number of S's or A's in the text but but not the number of #'s.

foreach(char A in text) Does not count the number of time 'A' appears in text.
foreach(char S in text) Does not count the number of time 'S' appears in text.
foreach(char # in text) Does not count the number of time '#' appears in text.

If you tried to use it like this as your post suggests, there is no way it actually worked correctly.

What this tells me is that you are trying to develop a program from scratch without first learning how to code, or at least how to code in C#. That never works for anyone and we tell people a LOT that they need to learn to code first, through books and tutorials and lessons. *Then* start developing software from scratch.

Let me say this though... It sounds like this is all VERY new to you. This type of thing is covered very early on in any self-teaching book. Which makes me think you really aren't ready to be designing an application yet.

Newbie/Rookie said:

I have a little programming experience but I need to write ...

You need to start there. I can't say "I have little experience in speaking Russian, but I have been assigned to write a mystery novel in Russian. Can you help me?"

We can help you by saying "First learn basic programming and the language of C#. Then take on assignments." Could someone here write this program for you? Sure. Could someone here map out all the processes you need to follow and do the Software Design part of this in the slim hope you could code it from there? Sure. But we don't volunteer to do the job that you're either getting paid for, or getting a grade for. You may want to read this.

For now, just work on the lessons. Do a self-teaching book from cover to cover. Then consider writing a program.

Don't try to create a useful working program to fit a need of yours (or a for-pay contract) as your introduction to coding project. When you are learning to code you don't know enough to code a program, let alone know how to engineer the architecture of a program. It would be like saying "I don't know how to read sheet music, or play an instrument. I think I'll write a 3 act opera as my first learning experience."

I don't say this to be mean. We've seen lots of new coders take this approach and we know it doesn't work. Trying to design your own programs before you understand the basics of the code language you've chosen just leads to problems, frustrations, and 'swiss-cheese' education (lots of holes).

---

Resources, references and suggestions for new programmers. - Updated Dec 2011

---

Spoiler

Quote

I already have a background in programming from this other software/technology/lanugage so I don't think I need to do tutorials

Here's how I look at doing tutorials even if one has a coding background that makes one think they don't need to do tutorials:

• If one's background really is enough to not need the tutorials, then they won't take long - So what's the harm?
  
• If the tutorials do take a while, then it might be time to re-think how much of one's old experience really applies to the new technology.
  
• There's no down-side. Every tutorial/series teaches something in a new way. Maybe you pick up a neat trick or a different approach to something that you already knew.

The stages of asking for homework help on a forum

Finding answers to specific problems:
Sometimes just knowing where to look can make all the difference. Google is your friend.
Search with either "C#" or "MSDN" as the first word: "MSDN Picturebox", "C# Custom Events", "MSDN timer" etc.
How to do a good search that will get you targeted answers.

Once you have that MSDN page that describes the function, you may not be familiar with out to actually get useful information from that page. There is a LOT of data there. So what is the important parts? Read this guide to reading the MSDN.

Don't think you are the first person to ask a question. Try a search on this site to see if someone has already brought up this problem. Also, as soon as you post your question go to the bottom of the updated page: You will see where the system has already analyzed your question and tried to find similar threads for the same question, so check those links out.

But honestly, just typing away and seeing what pops up in Intellisense is going to make your self-education take 20 years. You can learn by trying to reverse engineer the language through banging on the keyboard experimentation - or you can learn by doing the tutorials and following a good "How to learn C#" book. There are so many great "How do I build my first application" tutorials on the web... There are dozens of "Learn C# in 21 days", "My first C# program" type books at your local book seller or even public library.

Beginner:
C# Fundamentals: Development for absolute beginners
Build a Program Now! in Visual C# by Microsoft Press, ISBN 0-7356-2542-5 is a terrific book that has you build a Windows Forms application, a WPF app, a database application, your own web browser.

Martyr2's mega project ideas list is a great place to start on developmental projectst that you can learn from; rather than trying to make something complex like a game as a self-teaching tool {that never works for anyone}

Visual Studio Keyboard Shortcuts

D.I.C. C# Resource page Start here
Intro to C# online tutorial then here...
C# control structures then here.
MSDN Beginner Developer video series
MSDN video on OOP principals, making classes, constructors, accessors and method overloading
MSDN Top guideline violations, know what to avoid before you do it.
Design patterns as diagrams

I hate sending people to another site when we have such good tutorials here, but this series shouldn't be overlooked.
Programming OOP in C# - Part 1
Programming OOP in C# - Part 2
Programming OOP in C# - Part 3
Programming OOP in C# - Part 4
Programming OOP in C# - Part 5

Writing a text file is always one of the first things people want to do, in order to store data like high-scores, preferences and so on.
Writing a text file tutorial.
Reading a text file tutorial.

Have you seen the 500+ MSDN Code Samples? They spent a lot of time creating samples and demos. It seems a shame to not use them.

Intermediate:
The tutorials below walk through making an application including inheritance, custom events and custom controls, object serialization and more.
Bulding an application - Part 1
Building an application - Part 2
Quick and easy custom events
Separating data from GUI - PLUS - serializing the data to XML
WPF version (WPF-MVVM data binding)
Passing values between forms/classes
Decouple your multi-threaded work from the GUI so forms don't hang

Working with environmental variables
'Why do we use delegates?' thread
And everyone always wants to connect to a database, right out of the gate so Database tutorials right here on DIC

C# Cookbooks
Are a great place to get good code, broken down by need, written by coding professionals. You can use the code as-is, but take the time to actually study it. These professionals write in a certain style for a reason developed by years of experience and heartache.

Everyone:
Debugging tutorial
Debugging tips
Debugging in detail
Great debugging tips
It still doesn't work, article

I urge you to work through the C# learning series here on DIC, and to work a self-teaching book from cover to cover before you even think about designing your own applications.
Microsoft Visual Studio Tips, 251 ways to improve your productivity, Microsoft press, ISBN 0-7356-2640-5 Has many, many great, real-world tips that I use all the time.

These are just good every-day references to put in your bookmarks.
MSDN C# Developers Center with tutorials
Welcome to Visual Studio
Free editions of Visual Studio 2010

Windows Presentation Foundation:
Create Animations Programmatically

Let me also throw in a couple tips:

• You have to program as if everything breaks, nothing works, the cyberworld is not perfect, the attached hardware is flakey, the network is slow and unreliable, the harddrive is about to fail, every method will return an error and every user will do their best to break your software. Confirm everything. Range check every value. Make no assumptions or presumptions.
  
  
• Take the extra 3 seconds to rename your controls each time you drag them onto a form. The default names of button1, button2... button54 aren't very helpful. If you rename them right away to something like btnOk, btnCancel, btnSend etc. it helps tremendously when you make the methods for them because they are named after the button by the designer.btnSend_Click(object sender, eventargs e) is a lot easier to maintain than button1_click(object sender, eventargs e)
  
  
• You aren't paying for variable names by the byte. So instead of variables names of a, b, c go ahead and use meaningful names like Index, TimeOut, Row, Column and so on. You should avoid 'T' for the timer. Amongst other things 'T' is commonly used throughout C# for Type and this will lead to problems. There are naming guidelines you should follow so your code confirms to industry standards. It makes life much easier on everyone around you, including those of us here to help. If you start using the standards from the beginning you don't have to retrain yourself later.
  
  
• Try to avoid having work actually take place in GUI control event handlers. It is usually better to have the GUI handler call other methods so those methods can be reused and make the code more readible.
  
  Spoiler

  
  

  btnSave(object sender, eventargs e)
  {
      SavePreferences();
  }
  
  SaveMenuItem(object sender, eventargs e)
  {
      SavePreferences();
  }
  
  SaveContextMenu(object sender, eventargs e)
  {
      SavePreferences();
  }
  
  FormMain_Closing(object sender, eventargs e)
  {
      if (IsDirty) SavePreferences();
  }
  

  
  
  
• I strongly suggest installing VMware or some other virtualization technology on your development PC so you can create a couple virtual computers for testing. This would allow you to debug and test inside: WinXP32, XP64, Vista, Win7x32, Win7x64... etc. without having to actually have 5 physical PC's. Visual Studio will let you send the debug directly into one of these virtual machines so you can watch it operate, check its variables, see the crashes and so on just as if it were debugging on your real machine.
  
  
• This can't be stressed enough in today's world of cell phone messaging:
  Don't use txt/sms/leet/T9 speak like: u no, u r, dnt, wut i m do-n, coz, al gud, b4, ny1, and so on like this guy:
  
  dis not b d'hood dawg... You are sitting at a real keyboard with a real monitor, not a cell phone. You are not here texting your high school posse to come to your kegger after their shift at Taco Bell. You are here asking for help from senior coding professionals who graciously donate their valuable time to helping the next generation of coders with their chosen craft. Please try to show them, yourself and the industry some respect by writing at least at an eighth grade level. (IE: English not ebonics or SMS, real words, punctuation and so on). If you can't take your own problem/question seriously enough to write like an adult, then why would you expect anyone else to take it seriously?
  
  When you write a post you are presenting yourself. Your writing style is all you have to show others who you are and what you stand for. When I see posts filled with lack of capitalization, SMS text like 'Urself', lack of punctuation and so on; what I see is someone who just doesn't care to make even an eighth grade presentation of themselves. I also see that you feel we are not worth the effort. Posts that look like this show that you don't feel the person you are talking to is worth speaking to as an adult. If you show this level of contempt or apathy towards someone you are asking for help how can you expect to be taken seriously or expect to receive that expert's fullest attention and time to help you?

[RobinGoodfellow]

Thank you Gavisann I appreciate your reply but I do not yet understand how to solve this problem. I understand that I cannot name a variable # but all I want is to simply calculate the number of times the # symbol appears in a string which I know for a fact will have any given number of # symbols. Can I not use the foreach statement to do this? If not might you advise me on the correct way of going about this. Once again I appreciate your help =]

[tlhIn`toq]

Re-read post # 2.

Gavisann already showed you how to loop through each character of a text string.
Try actually running that code so you can learn what it does.

From there you just have to add an "if" statement within the loop and increment a counter int every time the char is the char you are looking for.


You said you were successfully counting the number of 'S' or 'A' that appear in a text string. Can you show us that code that is working for you? We can show you what to change to make that work. But I suspect that code didn't really work as you thought it did and want to confirm that.

[eclipsed4utoo]

Yes, YOU can use a foreach statement do accomplish what you are trying to do. However, YOU will need to do that. We try to avoid giving you the answer as that will simply allow you to copy and paste and not understand what is occurring.

Gavisann's answer is perfect as it shows you exactly how to loop through a string variable and print out each character. Now, you aren't going to be printing them out, but using that code, you *should* be able to determine what you need to do next.

[RobinGoodfellow]

tlhInq 'toq I appreciate your reply. You are right that I am not very experienced with C#. I have had a few years experience programming with Basic languages however it probably will not surprise you to know that this is my very first delve into OOP. This ridiculously simple function I am trying to write is essential to the completion simple text analyzation program which has been set as an assignment by my university (I am in my first year and this is my first C# assignment). I have written the rest of the functions for this program already and believe it or not several of these functions require utilization of the foreach statement in it's correct usage. The reason I have tried to use the foreach statement as a solution to my # symbol problem is that at the time being I simply do not know any other way. I do indeed have reading materials at my disposal but they are relatively useless to me given that I do not know exactly what it is I am looking for in them. My assignment is due on the 6th and this is the only part of it I have struggled with thus far and ironically I saved this part for last as I thought it would be the easiest. Perhaps if you could just point me in the right direction? Even if you could suggest a keyword I could look up in the index section of the dozen c# programming bibles I have lying around the room I would appreciate it! Honestly I am in desperate need!

[eclipsed4utoo]

There is no built-in way of doing what you are trying to do. YOU have to handle the logic yourself(which is what the assignment is teaching you). There is nothing for you to look up in a textbook or reference manual. You have been given code on how to loop through each character in a string. What more do you want?

[Curtis Rutland]

I'll give you a few hints.

foreach
if
char
string
++ operator

Read up on those links and you'll know everything you need to do this.

[RobinGoodfellow]

Thanks everyone for your help! In the end I simply used an Index.Of loop to find all instances of the # symbol in my string, no foreach required. =)

[RexGrammer]

Haha, hell of a way to make a glorious comeback!

On topic:

Are there any performance differences between the two solutions?

Solutions:

1. foreach with a counter
2. using IndexOf

This post has been edited by RexGrammer: 03 January 2012 - 12:33 PM

[Curtis Rutland]

The internal workings of IndexOf use some sort of loop. Therefore, using IndexOf in a loop means you're doing nested looping. Doing a foreach with a counter would be a single loop. That would be the "faster" way, but I doubt there would be any noticeable differences you could observe without a timer.

[RobinGoodfellow]

int count = String.ToCharArray().Count(x => x == '#'); // Count number of Hashes

In one line haha ;-)

[Curtis Rutland]

Well, yeah, but we weren't going to just hand him copy/pastable code. For the record, you can skip the ToCharArray call and it'll still work, string is already an IEnumerable<char>.