private void OpenClick(object sender, RoutedEventArgs e)
{
Microsoft.Win32.OpenFileDialog openDialog = new Microsoft.Win32.OpenFileDialog();
openDialog.DefaultExt = ".graph";
openDialog.Filter = "Text files (*.txt)|*.txt|All files (*.*)|*.*";
openDialog.Title = "Open graph from a file";
Nullable <bool> result = openDialog.ShowDialog();
if (result == true)
{
core.LoadFromFile(openDialog.FileName);
}
}
