Question

I have three pages with very similiar behaviour, so I made a User Control with 3 behaviours, I did this with adding an enum and a property of this enum type.

public enum ucType
    { 
        CustomersWhoHaveAContract, CustomersWaitingForContract, CustomerOfPreReservedContracts
    }

    public ucType UserControlType;

    protected void BtnLoadInfo_Click(object sender, ImageClickEventArgs e)
    {
        switch (UserControlType)
        {
            case ucType.CustomersWhoHaveAContract:
                DoA();
                break;
            case ucType.CustomersWaitingForContract:
                DoB();
                break;
            case ucType.CustomerOfPreReservedContracts:
                DoC();
                break;
            default:
                break;
        }

in my pages I assign a value to the UserControlType,

protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            ucCustomersWithContract1.UserControlType = UserControls.ucCustomersWithContract.ucType.CustomerOfPreReservedContracts;
        }
    }

but when I click the button the UserControlType is always CustomersWhoHaveAContract, meaning that it is losing it’s value. Where is the problem?

Answer 1

You mean ASP.NET WebForms, right?
Controls don’t get all their data automaticaly restored, there is ViewState mechanism.

MSDN article
http://msdn.microsoft.com/en-us/library/ms972976.aspx

To fix an example, change your field into property:

public ucType UserControlType {
   set {
      ViewState["UserControlType"] = value; 
   }
   get { 
      object o = ViewState["UserControlType"]; 
      if (o == null)
         return ucType.CustomersWhoHaveAContract; // default value
      else 
         return (ucType)o; 
   }
}

and it should work.