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What table????????
SG
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There's a toolbox in the designer. You should be able to click and drag one of many kinds of tables from there.
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I have an application where the user can enter a string to pass to the com port. A common string for this program is "W\r" with \r being carriage return.
When the program passes the string through the accessor, it shows up through the debugger as scaleStation.SendString = @"W\r". I don't want the literal value "W\r", I want "W" with a carriage return.
I ended up using the following for the solution, but was wondering if there is a better way to do this? I am worried the user may find another escape string that I may not have coded for.
string ss = scaleStation.SendString;
SendStr(ss.Replace(@"\r","\r"));
Thanks for your ideas!
Hogan
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The debugger is indeed showing it right! It's just showing the string representation of carriage return. The @ is to make sure that the '\' is not taken as an escape sequence. In essence, the Replace you do does not accomplish anything.
SG
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Maybe I didn't explain myself correctly, but the replace I put in the code did fix the problem.
I'll try again.
If I call the command SendStr("W\r"), it passes a Capital W and carriage Return to the com port. This works as desired as the device attached is expecting this string.
If I set a variable through a text box, I get the value @"W\r" passed literally to the device with no carriage return. So the command looks like SendStr(stringVariable).
Sample Application code: http://www.snorkie.com/codesamples/stringsample.txt
Set your breakpoint at line 105. Press the button and look at the value of the two variables s and s2 by putting your mouse over them or using the watch. You will see that they are different...
s = "W\r"
s2 = @"W\r"
Using the value from s2 won't pass the carriage return I need for my device. Converting s2 using the code s2.Replace(@"\r","\r") does give me the value I need.
So again, I have a solution, but I think there has to be a better one. Does anybody see a better way to do this?
Thanks
Hogan
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There are 14 different escape codes[^].
You can use the RegEx.Replace method with a pattern like "\\([\\0bfnrtv])", and a delegate to determine the replacement character, to replace them.
---
single minded; short sighted; long gone;
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Hello developers.
I need a help with clickonce deployment.
I my app it's has a *.mdf file, when I install my app the *.mdf goes to ...\Local Settings\Apps\2.0\... folder
But the app's folder has a complex name, as app...ex3ynnnnnadiGGGfzzzsds
Can I customize this name?
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Nope, I guess not. But in any case, you can dynamically get the folder name at runtime using Application.StartupPath. So why bother about the long folder name?
SG
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That actually doesn't work with a ClickOnce deployment. Content files, like an MDF file go into a very different folder from your executable. You can use the Deployment namespace to find the path to that folder (I forget exactly how right now), or I THINK you might also be able to cheat and use |DataDirectory| in the connection string (I haven't tried this yet!).
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The problem was solved 
Tks for all
When I attached the mdf file, I needed attach it as Data File
When I changed this option, everything works all right
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The only thing you need to do is have a server that will how the deployment. So if you were using a file share \\myServer\InstallAdministrator then just do the following:
1) Open your solution
2) Right click your project you want deployed
3) Choose Publish from the popup menu.
4) When asked give it the server location
You will get a web page that describes what is published and that is the URL you publish to your users. Voila, they click that url, they click Install, and in seconds they are running the application. From that aspect...who cares how things are named on the server since neither you nor the user will actually see the deployment folder day-to-day.
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I have been working on something in a project for the past few days, and I have been getting a little frustrated, and I have to decided to start from scratch. I am looking for some input on what I want to do, so any suggestions are certainly welcome.
I have a form which unzips data files, then calls an Import method from a class in a seperate project. When importing it uses SQLBulkCopy to copy all data in these files to a sql database. There is a large amount of data, so I need to keep the user informed of the progress during importation. So I want to display on the Form the data file name, count, and index while also displaying on a progress bar the percentage of data copied of the total amount from that file. This information will be updated on said form everytime a Batchsize is completed.
Input on how you would tackle this would be great.
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Well you definitely need to use multithreading to make you GUI responsive during the time-consuming unzipping operation. You need to use raise events from your worker thread to notify the GUI of the progress. There needs to be proper marshalling between the threads.
Maybe this link:
http://msdn2.microsoft.com/en-us/library/ms998490.aspx[^]
will give you some ideas.. Especially the section "Using Tasks to Handle Interaction Between the UI Thread and Other Threads" will be relevant to you..
Hope this helps,
Bijesh
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I would use a third party tool to take care of the SQL stuff. I use Red-Gate tools and have never had a problem with them. (No, I don't work for them) Red-Gate SQL Packager will package objects and data with an executable and supports command line.
Just my thoughts.
Hogan
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I've been asked to help solve a performance issue if I can. A person requires an application which can distribute, virtually simultaneously, to as many as tens of thousands of client applications, a small amount of data. The data will usually be a single integer, but it is critical that all of the client applications receive the data with the very least possible delay, and, if possible, at virtually the exact same time. It cannot be known beforehand exactly when the server application will be able to determine and broadcast the data. The client applications must link to the server application; wait; and all be able to react to the data broadcast immediately.
Has anyone here written such a set of applications, or is anyone familiar with what kind of architecture or approach is necessary to achieve this kind of performance?
All reasonable approaches are legitimate candidates for solution.
TIA
m
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I had to deal with a situation like this, but the data was coming from PLC's and we had an OPC server running on the server, the software running on the client side using an OPC client would subscribe to the item and receive data. All the clients would simultaneously get the data, the updates were pretty fast also(considering each client subscribed to 100's of items). You could probably try to google about OPC and find out what kind of architecture they are using to do it.
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OPC is described to be an open standard similar to OLE:
http://www.opcfoundation.org/Default.aspx/01_about/01_whatis.asp
OPC's Alarms and Events specification addresses issues most similar to those of my question, but does not appear to be a method for actual simultaneous broadcasting of data (in fact, it appears to be a pull technology, versus a push technology); and I am wondering if a "simultaneous" broadcasting technology exists.
I'm trying to get my brain around a low level concept that will provide the best achievable performance. It seems to me that any possible implementation (including OPC?) will still be subject to having to serially broadcast (or, in the case of OPC, request) the data.
I am assuming 1) that at best a server process is going to have to iterate an array of clients; 2) that consequently the number of supported clients can only inherently degrade process speed; and 3) that optimal speed can only be achieved by minimizing interaction.
If these assumptions are correct, then there is no practical way to "simultaneously" broadcast/expose the data, and a limitation for maximum possible performance exists. The performance ceiling therefore would be something like NumberOfClients x SpeedOfSingleBroadcast, whereas the speed of the desirable "simultaneous" broadcast is 1 x SpeedOfSingleBroadcast.
Does anyone have any further thoughts on this?
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This is a pretty good article on OPC:
http://blog.matrikonopc.com/index.php/thoughts-on-the-opc-ua-information-model/[^]
A few exerpts:
"A good starting point to understanding what the Information Model might represent, is to think in terms of the OPC Item address space, and Browsing interfaces in OPC DA. The specification described interfaces for viewing and navigating the address space (browse space). It did not dictate how the browse space was built or persisted in the underlying OPC DA COM server."
"In some cases the OPC Server did not persist this information, it simply made calls into the underlying native system to return the Items, like the OPC Server for Performance Monitor. In other cases the OPC Server would persist the information as a memory map, relational database or XML schema, such as the OPC Server for Microsoft Excel. In both cases it was transparent to OPC Client where the information came from."
This leads me to think we should be able to achieve OPC performance with standard .NET techniques.
?
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I would say that, your option of SingleBroadcast to all connected clients would give you the simultaneous broadcast to all the clients. OPC actually checks for all the clients connected and the items subscribed by the client and then send the required data, this would mean some lag of 1/1000 second or even lesser.
Does you software need to be that accurate in simultaneously sending data? We are taking about time in milliseconds to process a complete array of clients and sending data to them.
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Tarakeshwar Reddy wrote: I would say that, your option of SingleBroadcast to all connected clients would give you the simultaneous broadcast to all the clients. OPC actually checks for all the clients connected and the items subscribed by the client and then send the required data, this would mean some lag of 1/1000 second or even lesser.
Thanks for pointing this out, because it was not evident from the documentation I saw.
As to the "virtually simultaneous" requirement, these people are far from meeting their goal. Achieving the best practical performance subject to the limitations of such a process is as good as it's going to get for them, so that's what I'm interested in establishing. I haven't seen their code yet, so I don't know what they're doing. I assume their poor performance is a consequence of a fundamental problem such as mis-use of TCP/IP. They're having great trouble supporting a handful of clients.
I did find some interesting OPC components, and may write the company to determine if they can solve the problem if it looks like we can't solve the problem ourselves. Except perhaps for the number of clients, it seems this should be relatively simple, and that we should be able to avoid layering such substantial technology over such a simple application.
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Well - this could be a candidate for Sql Notification Services. Basically, you would have your applications register their interest in the data and then the update would be triggered at point A. Mind you, you are going to have a fun job updating that many clients "simultaneously".
Deja View - the feeling that you've seen this post before.
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This was one of my initial suggestions to these people -- the reservation being whether the underlying process can do the job better than a minimalized process we can write ourselves. I would think that to achieve best possible speed, we need to be able to spin off separate threads of execution to handle each callback. Each succeding broadcast then would not have to wait for conclusion of the preceding. Because the few threads available to the .NET thread pool would seem to preclude much advantage from multi-threading in a .NET server implementation, I was hoping that some "easy" integration of an RDBMS might circumvent the minimal available threads of the the thread pool. Is there an RDBMS you might recommend for being particularly strong in this area -- a good candidate for this job?
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Well, we've had some success in this area with SQL Server 2005 and Notification Services. To be honest, MS has invested a lot of money in this technology and done a lot of work on it to ensure its robustness. To get this level of robustness/concurrency in custom code you are going to have to do a lot of work that has already been done for you, and you will have to do an amazing amount of testing.
Deja View - the feeling that you've seen this post before.
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I'll take your advice quite seriously.
Thanks a bunch, Pete. I appreciate it.
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No problem. I'm glad to help.
Deja View - the feeling that you've seen this post before.
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