Question

When I want to press button it gives me error “key not found”. I want to have the default value of variable “dzien” = 0.

Imports System.IO.IsolatedStorage

Partial Public Class _1
Inherits PhoneApplicationPage
Private dzien As Integer

Public Sub New()
    InitializeComponent()

End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles Button2.Click
    dzien = CInt(IsolatedStorageSettings.ApplicationSettings("dzien"))
    Try
        dzien = CInt(IsolatedStorageSettings.ApplicationSettings("dzien"))
    Catch ex As KeyNotFoundException
        dzien = 0
    End Try
    If dzien = 0 Then
        TextBox1.Text += "dzien jest 0 !"
    End If
End Sub
Private Sub Class_1_Unloaded(ByVal sender As Object, ByVal e As System.Windows.RoutedEventArgs) Handles Me.Unloaded
    IsolatedStorageSettings.ApplicationSettings("dzien") = dzien
End Sub

End Class

Answer 1

Remove the first dzien = CInt(IsolatedStorageSettings.ApplicationSettings("dzien")) line. It should look like this:

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles Button2.Click
    Try
        dzien = CInt(IsolatedStorageSettings.ApplicationSettings("dzien"))
    Catch ex As KeyNotFoundException
        dzien = 0
    End Try
    If dzien = 0 Then
        TextBox1.Text += "dzien jest 0 !"
    End If
End Sub