Question

Right now i am developing a Windows phone app, yes this is my first windows app. Right now i am facing an issue, don’t know what’s the silly mistake i made. Yes of course i have done debugging.

Now, what exactly i am doing?

1. Passing data from 1st page to 2nd page,
2. On the page, catching data inside onNavigateTo() method, yes i am receiving it correctly.
3. Based on the parameter/data (i.e. ID) i got, i am making web service call.

Problem:
If i move to the 3rd page from 2page and again came back to the 2nd page, its again making web call. i.e. calling DownloadStringAsync again in below code.

i.e. If 2nd page is having ListBox with 5 data, now clicking on particular item i am moving to 3rd page, if i came back to 2nd page from page 3, items get doubled i.e. 10 items (just because its making call again)

Here is the possible code for the reference:

protected override void OnNavigatedTo(NavigationEventArgs e)
{
       base.OnNavigatedTo(e);

       type = Convert.ToInt32(NavigationContext.QueryString["Type"]);
       if (type != 0)
       {
           if (NetworkInterface.GetIsNetworkAvailable())
           {
              client.DownloadStringAsync(new Uri(Utils.Constant.WebService_URL));
            }
            else
            {
                    MessageBox.Show("Please check internet connection!!");
            }
        }
}

Answer 1

Can’t you use the following code to test if the user used the back button?

e.NavigationMode == System.Windows.Navigation.NavigationMode.Back