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When we create database connection in C# lets say to SQl server, why it is recommended to use connection statements within using? I know using makes CLR reclaims memory when control is coming outside of using by calling Dispose(). But SQL server connection should be a managed code and using is usually used for unmanaged code. I mean we create SQL Server connection objects from .NET libraries, so why is unmanaged? Really looking for answer.
Favourite quote:
In youth we learn, In age we understand.
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munishk wrote: using is usually used for unmanaged code.
Hehe, as you said yourself, it's not limited to unmanaged code.
munishk wrote: I mean we create SQL Server connection objects from .NET libraries, so why is unmanaged?
Unmanaged code often holds handles, and other stuff that needs to get rid of "exactly once". A library is loaded once, and unloaded once.
For a SqlConnection it adds other benefits; not only does it close the connection once the object gets disposed (something that should be done "once" again, in a destructor-type method), it also clears the largest fields (and disposes embedded disposables), helping the GC.
Bastard Programmer from Hell 
if you can't read my code, try converting it here[^]
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Eddy Vluggen wrote: For a SqlConnection it adds other benefits; not only does it close the connection...
Not generally it doesn't. It returns the connection to the pool. If the pool is configured explicitly (non-default settings) then it will.
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But can we say that creating sqlconnection is unmanaged resource? This is even stated in Albhahari book too. I am still looking for clear answers.
Favourite quote:
In youth we learn, In age we understand.
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There's got to be unmanaged objects deep in there somewhere -- named pipes, network sockets, I don't know.
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munishk wrote: But can we say that creating sqlconnection is unmanaged resource?
No you can't say that because it is managed class.
At some point that class or some other part of the .Net API (not visible) is interacting with unmanaged resources. Just as many other managed classes do.
However that has nothing to do with your use of it.
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munishk wrote: SQL server connection should be a managed code
Why should the connection be managed code?
Why is common sense not common?
Never argue with an idiot. They will drag you down to their level where they are an expert.
Sometimes it takes a lot of work to be lazy
Please stand in front of my pistol, smile and wait for the flash - JSOP 2012
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using is not just for unmanaged code - in fact I almost never write unmanaged code, and I use using all the time.
What is does is ensure that the object created in the using block header is Disposed at the end, exactly as if it had been written as
MyObject mo = new MyObject();
...
mo.Dispose(): In fact, a using block is just a syntactic sugar for just that, but with the added advantage that it terminates the scope of the variable as well, so you can't accidentally use the Disposed object.
Why do I use it? It's clean, it's clear, and it de-scopes a variable when I can't use it again.
Why is it important to Dispose managed objects? Because some of them hold resources: for example, Bitmaps, Files and so forth hang on to resources such as handles and file access locks until the object is disposed - in the case of a Bitmap it is not at all obvious that:
Image i = Image.FromFile(path); puts a file access lock on the image source file until the image is Disposed. So if you use this to load an image, let the user modify it and then try to save it again, the file may or may not still be in use...annoying. Surrounding the Image creating with a using block removes this problem.
If an object supports IDisposable, then Dispose should be called on it. And a using block is the easiest, cleanest way to do that.
Ideological Purity is no substitute for being able to stick your thumb down a pipe to stop the water
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munishk wrote: why it is recommended to use connection statements within using?
It isn't; I don't do it that way anyway. I dislike code that keeps instantiating and disposing Connections and Commands over and over again for no good reason. I prefer to instantiate each once and hold onto it for the duration -- opening and closing the Connection as needed, setting the CommandText, etc. But that's because of the type of systems I write; your systems may not benefit from it.
Additionally, I wrap Connections and Commands in my own classes which implement IDisposable, so when it makes sense to (mostly console utilities) I instantiate my class with a using statement:
using
(
PIEBALD.Data.IDatabase db
=
new PIEBLAD.Data.SqlServerDatabase
(
...
)
)
{
...
}
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As per the the title, I am taking over a project from QIOS DevSuite which included many useful free controls such as a Winforms Ribbon Control etc..
I want to keep this control free to the public, but I can't do it all on my own!! The reason for my post is, I am trying to build a community of volunteers to help with future development (like how phpbb is developed now) and support.
Currently QIOS have taken the control off line, but they have so far provided me with the forum and previous data etc.. So, if this is of interest as a small hobby then please get in contact with me at www.forum.qdevsuite.com.
Here is a link to screen shot of the qdevsuite http://www.qdevsuite.com/home3.gif[^]
Thank you
Dan
(Mods please delete if I have broken any rules, Sorry!)
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Santa's Little Helper wrote: (Mods please delete if I have broken any rules, Sorry!)
Whehe, yeah, just post blindly and let the mods clean up after you.
You should have posted in the collaboration-section, the menu is on the left side of your screen 
Bastard Programmer from Hell 
if you can't read my code, try converting it here[^]
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I know, but I wasn't too sure, and didn't want to offend anyone.
Thanks, I will try that section as you suggested.
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Hi, I have MS Visual Studio 2010 and I program in C#. I need a good looking, prebuilt UIs for my entire application. If you know some resources I'll be glad if you tell me. Thanks.
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Web, Windows Forms, WCF? Resources for each can easily be found by searching on google. You are probably not going to find prebuilt UIs, however, as each application will present its own set of challenges and customization. After all, if all the UI's were to be prebuilt and existing, then the underlying application is likely to have been built along side it and you would be able to purchase or download the complete application negating the necessity for you to write it in the first place....
I wasn't, now I am, then I won't be anymore.
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You're right but I'm too close to the end line of the project. Therefore I didn't have another choice cause of lack of time. Thanks, by the way
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You haven't said what the application does, or what technology it is. This may seem minor to you, but it will affect the answers you get if you don't provide vital information.
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The application itself is based on WinForms. I needed an alternative for buttons, message boxes and so on. Now, I, by myself, have found Telerik RadControls pretty useful, finally after too much googling
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atoi_powered wrote: I, by myself,
That is because you asked for an entire UI, you should have asked for a control suite. Telerik is a good choice, there are quite a few others out there as you have no doubt found.
Never underestimate the power of human stupidity
RAH
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As CodeProject doesn't have a telepathic interface installed yet, you would have to find this out for yourself. The moral here, if you want useful help, ask a decent question.
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I am looking for good example or articles where Database programming with all operations on multiple tables is depicted using Isolated Storage.
Please suggest some good articles.
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SqlConnection conn = new SqlConnect(
"Integrated Security=SSPI;Data Source=DBSRV1;Initial Catalog=master");
SqlCommand cmd = conn.CreateCommand();
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = "sp_attach_db";
cmd.Parameters.Add("@dbname", SqlDbType.NVarChar, 128).Value = "MyDB";
cmd.Parameters.Add("@filename1", SqlDbType.NVarChar, 260).Value =
@"C:\Program Files\Microsoft SQL Server\MSSQL\Data\MyDB.mdf";
cmd.Parameters.Add("@filename2", SqlDbType.NVarChar, 260).VAlue =
@"C:\Program Files\Microsoft SQL Server\MSSQL\Data\MyDB.ldf";
try
{
conn.Open();
cmd.ExecuteNonQuery();
}
finally
{
conn.Close();
}
This is OK but i need to get the DataBase Name and File Name from TextBox,i Tried but its not working any Help
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pranee24 wrote: i Tried but its not working any Help
Without seeing some of your code we cannot begin guess what is not working.
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pranee24 wrote: i Tried but its not working
Does not tell anyone what you tried or why you think it's not working.
Why is common sense not common?
Never argue with an idiot. They will drag you down to their level where they are an expert.
Sometimes it takes a lot of work to be lazy
Please stand in front of my pistol, smile and wait for the flash - JSOP 2012
modified 12-Jul-12 14:39pm.
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