It could be that is what Angela (OP) wants, however what is shown is that after Z9999 is AA000. I.e., as the length of the alpha part of the string gets longer, the numeric part gets shorter. The total string length remains 5.
Hi guys. StreamWriter.WriteAsync exists in 4.5 but not 4.0. I'm getting a sporadic error- out of memory exception, when I use StreamWriter.Write(String Builder). I'm not sure if I can move up to 4.5 yet, what's a good work around for 4.0?
How big is that freaking StringBuilder?? If you don't specify a size, it starts with 16 characters and allocates a new array internally every time you exceed it's capacity. So, it starts with 16, then goes to 32, 64, 128, 512, 1024, ... when you get into VERY large objects, you can be allocating megabytes of memory and possibly hit a size where the CLR doesn't have a big enough contiguous block of memory to fit the new size.
This also applies when you finally call .ToString on the StringBuilder. A new String object has to be allocated and the data in the StringBuilder copied to it. Again, if sufficiently big, the new String may not fit in memory because of a fragmented large object heap.
The CLR will allocate any object requiring more than 85K (IIRC) out of the LOB. The LOB isn't compacted and defragmented like the Smaller Object Heap is. So if you're allocating and freeing a bunch of large objects, you could be fragmenting the LOB to the point where you can't allocate a new object of the size you need, even though there's enough TOTAL free memory.
But, the way around this little problem using StringBuilder is to allocate the StringBuilder with a size sufficient to hold the entire POSSIBLE string without having it constantly reallocate itself.
Oh! And as for the StreamWriter.WriteAsync, there is no equivilent in any other version of .NET. You'd have to implement an Async version yourself. But, I don't think that has anything to do with your problem right now.
I want to ask something about radio buttons in a web page. I'm using c#.net.
Let's assume that I have a table with 5 rows and 3 columns. I put a radiobutton in each cell of this table. So we have 15 radio buttons.
The user should select exactly one choice in each column, and at most one choice in each row.
I tried radiobuttonlist in each row. But in this case the user can select more than one choice in a column. Or the user can not give up a selection in a row.
I think that I need to write a client-side script. But I could not figure out this problem in a practical way. I wish I had a control that solves this problem.
The radiobutton list in each row seems like a good approach because it handles one of your constraints: at most one choice in each row.
To handle the other constraint (exactly one choice in each column) you need to make a handler that's called whenever the selection state of a radio button changes, then check this constraint in the handler. If it's violated (i.e. more than one choice in a column) you can give the user an error message or change their previous selection in that column.
When they're done (e.g. they press the OK button), then you can check to see if every column has a selection.
hey guys !
can you guide me ,how can i write code in good ways!?
well lemme explain whats my problem !
i thought writing codes is most simple part of developing ,but after some project which i did ,i found that need to change my coding style !
as you know for one porpuse is many way to achieve ! but i found always choose worst way !
well is any book or reference to teach me how i choose best way? at least better way!
Bugs tend to appear in unclear code. They're harder to find there too. Maintenance of unclear code is more expensive. Unclear code is unreliable.
Try to make your methods short. As a method grows in size, its complexity increases faster than linear. If a method is becoming too large, break it up into 3-5 subroutine calls.
Start with designing the GUI. This will guide the rest of the development.
Don't feel bad if the approach you took was the worst one, because you'll learn from this experience. All programmers go through this. Try to summarize what you've learned in a simple rule you can follow to avoid this problem in the future.
Algorithm selection is a more complex topic. A course (or book) on data structures will also cover the most common algorithms used on these structures. These are also graduate courses specifically on algorithms.
(If you haven't already studied data structures, you should. It's one of the more important areas that you'll use on all but the most trivial programs.)
I always start with the data model design. I've found that starting with the GUI tends to influence bad practices in the data model or breaks even breaks it to the point where you need to toss it out and start from scratch.
There are many approaches and many problem types. There's no one correct approach for all problems, and each individual has their own style.
In each approach (GUI first or data model first), you can make discoveries that invalidate your previous design. Experience lets you anticipate more accurately the needs of the other half, while designing the first half.
In this case, I was answering a beginner's question. This person is unlikely to be dealing with a complex data model, and the needs of the GUI would probably be clearer, and would point the direction to go with the data model to support the GUI.
In my biased opinion, the primary purpose of an application is to satisfy the users' needs as well as possible, and letting the data-structure decisions steer you into a less-optimal GUI detracts from this.
well lemme explain whats my problem !
i thought writing codes is most simple part of developing ,but after some project which i did ,i found that need to change my coding style ! as you know for one porpuse is many way to achieve ! but i found always choose worst way !
There are a lot of ways to do something, and even we bicker about what is "best". And most of us here will have some "old code" somewhere from years ago that makes 'em go "wtf" today.
Always ask an explanation if there's an opportunity to do so.
well is any book or reference to teach me how i choose best way? at least better way!
You might want to download FxCop; it checks your code using pre-set rules. Another sweet way of learning alternatives is to read existing code (I love meeting new brownfields!) and, again if possible, ask for explanation if something is interesting.
Get lots of practice. Start your own open-source project, so that you'll be forced to "maintain" your own code.
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
Start thinking about how "programming" skills overlap with the non-programming things you do. Draw on your experience in the other areas of your life to help you improve. For example, work on your writing. Coding is composition and all the rules you learned about writing well apply to your programming: say what you mean; don't use a 10-cent word when a 5-cent word will do; don't mix metaphors (i.e., models); etc.
Hey there! I'm trying to write into a command prompt window (Not the debugger) from my C# GUI with no luck (I've looked at lots of examples), and I'm not sure where I am going wrong. The command prompt window will open, it will accept text if i type it in from my keyboard, but it won't accept it from my application.
I've tried with both the windows command prompt, and the custom one we are trying to write into. Long story short I am trying to access an AtmelAVR programmer from command line to automatically program devices in our assembly process. I can automatically program by command line when I enter the text myself, I just can't get out GUI to do it... I've attached my code below:
EDIT: Working in VS2010 on Windows 7
Any help is greatly appreciated!
Process PrgCommandPrmpt = new Process();
PrgCommandPrmpt.StartInfo.UseShellExecute = false;
PrgCommandPrmpt.StartInfo.FileName = "C:/Program Files (x86)/Atmel/Atmel Studio 6.0/extensions/Application/StudioCommandPrompt.exe";
PrgCommandPrmpt.StartInfo.RedirectStandardInput = true;
PrgCommandPrmpt.StartInfo.RedirectStandardOutput = true;
PrgCommandPrmpt.StartInfo.RedirectStandardError = true;
PrgCommandPrmpt.StartInfo.CreateNoWindow = true;
PrgCommandPrmpt.EnableRaisingEvents = false;
PrgCommandPrmpt.StandardInput.AutoFlush = true;
StreamWriter inputWriter = PrgCommandPrmpt.StandardInput;
StreamReader outputReader = PrgCommandPrmpt.StandardOutput;
StreamReader errorReader = PrgCommandPrmpt.StandardError;
tboxVerbose.AppendText("Doing stuff now!"); //This just outputs to a textbox to let me know something is happening.
string CommandText = "cd..";
inputWriter.WriteLine("WHY DONT YOU WORK"); //These are the two latest ways I tried to write to it, no luck.
PrgCommandPrmpt.StandardInput.Write(CommandText);//These are the two latest ways I tried to write to it, no luck.
I just tested that sample and it works fine. I would suggest you check some of the options you have selected to ensure none of them is conflicting with what you are trying to do. You could also take that working sample and modify it to use the command you wish to run and see what happens.
I'm not sure that we are trying the same thing here. I loaded that example into a new app, and it doesn't write to the console either. I also get an error on this line about a NullReferenceException, presumably as the buffer is empty?
inputText = Console.ReadLine();
if (inputText.Length > 0)
What "Settings" are you referring to when you said I should check the settings?
Well I'm not sure what you are doing wrong. I just copied the code from the link I gave you, then wrote another program that reads and writes to the standard input and output stream, and it all worked. Maybe the fault lies with the program that you are trying to execute; what exactly does it do?
The program we are trying to write into is just a CMDPrompt that has been written to access the programming functions of the AtmelAVR programmer through command line. The commands we need to send resemble the one below:
Nor would it, that just runs an independent process, which changes directory and immediately terminates without producing any output.
I have to say you are maybe getting yourself tied in knots here, by repeatedly trying everything you can think of, without really looking at what you should be doing. Think about what program you are trying to run, how it must be started, what input data it may read and what output it may produce. That should then determine how you need to start it, whether you need to feed it any input (beyond its initial parameters) and whether you should expect to read from its output stream.
Yeah, We are using a command prompt, or command processor as someone just called it (I may be using the wrong name for it). Then all re need to do is to literally send in a line (string) with a carriage return, read the text that comes in, and repeat based off of the text that comes back.
When I started it seemed easy enough to do, but it now seems that its not easy to feed text into a cmd window.
but it now seems that its not easy to feed text into a cmd window.
Yes, it's perfectly easy, but you need to understand what is happening in that window, as I explained in an earlier post. I have not used the Process class before, but by following the rules, and understanding what goes on in the started application, I demonstrated that it works as documented.
Not really. You start the command window, send it a (meaningless) word and then immediately close it. Maybe if you explain exactly what your program is supposed to do, I can offer some more suggestions. Explain:
How is the program invoked manually from a command window.
What, if any, further input commands do you need to type in to the program.
What output is produced by the program on the command window, that you need to capture.
What command, if any, is used to terminate the program.
The answer will not be forthcoming before tomorrow, but I'm sure it's possible to do it.
OK, I am starting to understand the issue. I had noticed it looked like there were two windows for an instant, but i attributed it to one of the Win7 window effects. So what is likely happening is there are actually two windows, and the one just opens and closes so fast that I can't see it?
To use the 'atprogram' the only route i can find into it is to use the StudioCommandPrompt located here "C:/Program Files (x86)/Atmel/Atmel Studio 6.0/extensions/Application/StudioCommandPrompt.exe". Once its open I need to run these commands:
After each step the window spits out some pass fail information.
There are alternative command line programming options, but that is the one I learned first.
This all makes a lot more sense now that I know the window is opening and closing very fast, it actually explains a lot. We're at the end of the day here, but first thing in the morning I'll try pumping in program commands like that and see if it works.
This whole time I saw an idle window sitting there, and assumed it meant the input hadn't been received.
Thanks for your help and patience, I will update tomorrow morning.
Yeah, AVR wasn't my decision, but that's another story. The C# GUI is part of an automatic test rig that tests all the functionality of our boards, then programs various aspects of the boards. It tests (currently) 7 boards at a time, but we will soon be expanding it.
Everything but the automatic programming is already working. I left it for last because I thought it was going to be the easy part :P