Persistent values in c#.NET

Hi,

I am trying to implement a page where, when you press a button, the value of an object field changes persistently.  For some reason, it does not do so now.  I have a feeling I'm missing something obvious.  

On the page, the object Test gets instantiated. The default value for the field mystring is "Init".  When the user presses the first button, the value gets updated to "new string". When the user presses the second button, the value reverts back to the default, which is NOT what I want to happen.  The value should stay the same.  What am I doing wrong?

Here's the code:

public class Test
{
    public string mystring = "Init";
}

public partial class TestPage : System.Web.UI.Page
{

    Test myTest=new Test();

    protected void Page_Load(object sender, EventArgs e)
    {
    }

    public void Button1_Click(object sender, EventArgs e)
    {
       myTest.mystring="new string";
        Label1.Text = myTest.mystring;
    }

    public void Button2_Click(object sender, EventArgs e)
    {
        Label1.Text = myTest.mystring;
    }
}
EffinGoodAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

PagodNaUtakCommented:
The reason why the string reverts to the original value is because all objects in ASP.Net Webapplication is destroyed once the page is created. Please see this link for more details
http://msdn.microsoft.com/en-us/library/ms178472.aspx

So as a work around you can store the class in viewState then retrieve that value upon page load to intialize the class again.

Please see the below code:  


 [Serializable]
    public class Test
    {
        public string mystring = "Init";
    }

   public partial class TestPage : System.Web.UI.Page
    {
        Test myTest;

        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                myTest = new Test();
                ViewState["test"] = myTest;
            }
            else
            {
                myTest = (Test)ViewState["test"];
            }
        }
        public void Button1_Click(object sender, EventArgs e)
        {
           myTest.mystring = "new string";
           Label1.Text = myTest.mystring;
        }

        public void Button2_Click(object sender, EventArgs e)
        {
            Label1.Text = myTest.mystring;
        }
    }
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
ASP.NET

From novice to tech pro — start learning today.