C# app stop executing and release reosurces

13y6.9kVisual Basic .NET

I have a C# 2008 windows/console application that I need to support that never seems to stop running. This application
seems to not release resources also. This application does not close connections also.

Thus can you show me in code, tell me, and/or point me to a reference that will answer the following questions:
1. How can I force a program to stop running?
2. How can I have the application release resources?
3. How can I have the appliction close connections?
4. Of the steps listed above, can you tell me the order of how these ending operations should occur?

7 Replies

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Vulpes13y ago
Accepted answer
I don't know of any windows which can tell you whether connection objects are open or not because this will depend on the object's internal state. As I said in my previous post, the object may expose properties which tell you what that state currently is but, as different objects may have different properties, you'd need to query the object directly to find out what the current state is.

Regarding your other questions:

1. You could deploy the application in debug mode if you think there may still be bugs and the users don't mind acting as 'testers' (in effect). If you do this, then the application may execute more slowly than it otherwise would but there shouldn't be any other problems.

2. If by 'everything' you mean stuff which is superfluous to the final application or which you'd prefer not to deploy for some other reason, then I don't see any particular problem with this except that the application will take up more hard disk space than it otherwise would.

3. If you're having problems trying to open files which are already open, then code which is simply looking at file names in a particular folder is unlikely to be the problem. The most likely reasons are that you've forgotten to close the file when opening it previously or it's already been opened by another application.
dc13y ago
To be able to tell what objects or connections are open when the application is about to end, I placed a break point in the code before the application ended.

I looked in the 'locals' window and the only thing I was was the parameters that were passed to the application when it first started.

Thus my question, is there other window(s) I can use to see what is open before the application finishes executing?

If there are other windows can you tell me what window(s) to use and give me an order of what is the best debug window to use?

I want to mention the following also:
1. An experienced contract told me I can deploy this application to production in debug mode since it is a low volume application. Could this be a problem? If so, can you tell me how to reoslve the issue?
2. Also when I deploy the C# 2008 application using the setup and deployment methods (not availalbe in vs 2012), I deploy everything? Could this be a problem? If so what should I deploy?

3.This application looks at filenames but does not open the files. Could this be an issue?
Vulpes13y ago
Some types of connection may have a State property or an IsOpen property which enables you to tell whether the connection is still open or not.

Also, even if they're already closed, calling the Close() method again may not be a problem - it'll just be ignored.

However, I'd look at what happens when the application ends normally and just reproduce that code (or call the appropriate method) before you attempt to end it abnormally.
dc13y ago
The following additional questions are as follows:
1. How can I tell what the additional connections that could still be open are?
2. How can I tell what connections are still open?
Vulpes13y ago
1. If you have any connection objects or other objects which you know use unmanaged resources stored in fields within your forms, then just close or dispose of them:

conn.Close();
someobject.Dispose();

You should be doing this in any case before closing the application 'normally'.

2. If you wouldn't have needed to do anything to disconnect from the web service if the application were closing normally, then you have nothing to fear from using Application.Exit() or Environment.Exit(1).

3. A sign that you may be using code to write to the registry is the presence of this using directive:

using Microsoft.Win32;

Apart from that look for the use of classes such as Registry or RegistryKey.

4. TBH I don't know whether setting integrated security = true in the database connection string will cause the registry to be written to or not. You could try setting it to false to see if it makes any difference.

5. In my experience if you have applications that won't close, the most likely reason is that you have subsidiary foreground threads which are still running and keep the application alive when the 'main' thread ends. If you're creating threads explicitly, you could try setting their IsBackground property to true (the default is false) before starting them.
dc13y ago
Thanks for your answer so far!
I have the following additional questions:

1. You mentioned the following, "Before calling either of these, I'd try closing all connections manually and releasing unmanaged resources by calling Dispose() on any object still in scope which implements IDisposable.".
Can you show me some code on how to accomplish this goal?
2. This appllication calls a web service. If I use either Application.Exit(); or Environment.Exit(1); , would that affect the connection to the web service? If so, is there other code I should use to solve the problem.
3. This application just went into production a few days ago for my small company. There are messages that the network admin found where the application is trying to write to registry keys. I did not think this application wrote to the registry keys but it must. What can I look for to see how the application is writing to registry keys?
4. Could the registry key problem be due to setting integrated security=true on the database connection? Do you think if the integrated security= false and an sql server application user is setup, would this solve the problem?
5. Overall, what do you think the best solution and can you show me code on how to solve this problem?
Vulpes13y ago
To stop the application running, I'd first try:

Application.Exit();

and, if that doesn't work:

Environment.Exit(1);

Before calling either of these, I'd try closing all connections manually and releasing unmanaged resources by calling Dispose() on any object still in scope which implements IDisposable.

Managed resources will be cleaned up automatically by the CLR when the application ends.

It's also likely that the operating system will be able to release unmanaged resources (file handles etc) when the process ends but I wouldn't rely 100% on this.