C# static variables persisting through vs2012 sessions, static variables NOT initializing correctly on re-run.

Najam uddin,

Thanks much.  I tried to use the constructor (failed) but want to try again with more knowledge...

The reason I failed was I could not figure out where to instantiate an object of the class before anything else ran, in other words what which page runs first.  I have read on this "singleton" pattern, I think I can attempt to instantiate it in all the required places and  only the first one will execute, setting my default properties. On each run.  My fear is the static class will still be instantiated on re-run.  I am trying to test this now.

Please if you have better solution or comment on this approach or...

Kind Regards
Sam

public class ResetConnectStringToDefault //Singleton
    {
        private static ResetConnectStringToDefault instance; //declare var instance
        private ResetConnectStringToDefault() //do class initialization stuff
        {
            // run set the defaults
        }
        public static ResetConnectStringToDefault Instance
        {
            get
            {
                if (instance == null)
                    instance = new ResetConnectStringToDefault();
                return instance;
            }
        }
        public static bool TriggerReset
        {
            // I do not have access for "new ResetConnectStringToDefault" due to protection level, so maybe if I access the public method it will trigger the constructor the first time??
        }
    }

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Najam uddin,

Thanks again, static constructor seems to be working in my test snippet, I am implementing it now into my project, I am pretty sure it will solve my issue.

Yes I want it to reset on re run, poor English on my part.

Kind Regards
Sam

käµfm³d 👽,

...because I ran the program again, so I expected

public static string s = "NOT initialized"; //my default value

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to be run and initialize again, to Not Initialized, later it gets Initialized to the proper value dependent on where the code is being run.

I see I should have used

public static string s = "Set to default"; //my default value

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and

 s = "Set to run";

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.  That would have made a much clearer question.  I would have expected it to be "Set to Default" instead of persisting at "Set to run"

Thanks
Sam

käµfm³d 👽,

With respect Savant, from newbe,  If you test the small snippet with vs2012 you will see the static variable persists between debug sessions of F5 and Shift+F5 and F5 again, break at breakpoint it persists the value from the prior run and does not go back to the default value.  

I am in an asp.net webpage environment.  I read that the static variables persists while the app domain is live?  Although I do not understand app domain, maybe IIS is the app domain??  

I am persisting this question as I want to understand and maybe help someone else with the same confusion.

Kindest Regards
Sam

käµfm³d 👽,

Just got your ps...

I have done it 50 + times.  I am familiar with the last successful build dialog, and always "NO" get my build errors fixed and then run again...

Thanks Much
Sam

Najam uddin,
käµfm³d 👽,

Sorry for not being verbose at the beginning, I thought it was simple.  Below is a small sample demonstrating my issue.  I moved to a static class and used the static constructor as Najam uddin suggested.

The following test procedure demonstrates old static values persisting on subsequent "Run[s]".

1. F5 Run, the label = "Default", ...Expected
2. click button, the label = "Not Default", ...Expected
3. shift + F5 Stop,

F5 Run, the label = "Not Default", ...NOT Expected, I expected "Default". I thought it should have run the constructor, but its instance must still be persisting so it did not??

This behavior persists if I close the browser
This behavior does not persists if
1. edit any code
2. rebuild
3. stop IIS
4. stop and relaunch vs2012

Thank You for sharing your experience and helping me solve this issue.
Sam

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Scratch_Debug.aspx.cs" Inherits="WebApplication1.Debug.Scratch_Debug" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:Label ID="lblStaticTest" runat="server" Text="lblStaticTest"></asp:Label><br />
        <asp:Button ID="btnSetS" runat="server" Text="btnSetS" OnClick="btnSetS_Click" />
    </div>
    </form>
</body>
</html>

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namespace WebApplication1.Debug
{
    public partial class Scratch_Debug : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack) 
            {
                StaticTest StaticTestInitialize = new StaticTest(); //execute static constructor
            }
            lblStaticTest.Text = StaticTest.s;
        }

        protected void btnSetS_Click(object sender, EventArgs e)
        {
            StaticTest.s = "Not Default";
            lblStaticTest.Text = StaticTest.s;
        }
        
    }
    public class StaticTest
    {
        public static string s
        {
            get
            {
                return _s;
            }
            set
            {
                _s = value;
            }
        }
        private static string _s;
        static StaticTest()
        {
            _s = "Default";
        }
    }

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käµfm³d 👽,

Thank you for your above Comment.  I got Friday through Monday off for "Veterans' Day" sorry I did not get right back to you.

No changes to the code previously submitted.

I get the same behavior after reinstalling vs2102.  So I decided to..
Test on two other boxes
Upload to a test server running Server 2008 and IIS 7
--Test from three different boxes both local and remote on the above Server 2008 and IIS 7
Got permission to have anonymous viewing set on that folder and send the url  to you http://vince.orodev.com/debug/scratch_debug.aspx. (READ BELOW  BEFORE CLICKING THE LINK BECAUSE YOU ONLY GET ONE CHANCE TO SEE.)

1.  If you go to this url it will initialize at "Default"
2.  Click the button to set the static object property to "Not Default"
3.  Do anything, like new tab, new window, new browser,  clear cache, reboot...

You will observe the label showing the static object property will NEVER return to "Default".
This confirms for me (same as stepping through the code with vs) that the object's constructor is not executed ever again (even with "new" ), so we always have "Not Default".  (note: in these tests on IIS 7 there is no vs2012 involved.)

The only way I found to get it back to "Default" to test again, is:
1.  upload my files again (no changes required.)
2.  recycle the application pool
3. restart IIS 7

I will upload my files to reset things to default, as soon as I submit this "Comment" so you can see  for yourself.  It will only show "Default" once and then be stuck at "Not Default".  Let me know and I will reset things if you need.

Thanks Again.
Sam

käµfm³d 👽,

That is what I was expecting, everything is working correctly.

Thank you for the link.  I am sure this has been my issue (me not understanding how iis works).  I am still digesting the link...

I think I need to set "Idle Time-out (minutes)" shorter.   Is there an idle flag I can access?  Is the Idle Time-out "n" minutes from the last Request?

Thank you.

Regards
Sam