windows phone application button content - windows

Question

I've got incredibly weird problem. I'm making memo game app on windows phone. When I click 2 buttons and if they have the same content they should collapse. Problem is that even if they have the same content for example 1 it shows me that this statement is false! Like 1 was not equal 1.
Here's the code:
public partial class Memo : PhoneApplicationPage
{
private int points = 100;
private string[] numbers={"a","a"};
private Button selected_button;
public Memo()
{
InitializeComponent();
button1.Content = numbers[0];
button2.Content = numbers[1];
}
private void button1_Click(object sender, RoutedEventArgs e)
{
if (selected_button != null)
{
PageTitle.Text = "" + selected_button.Content + " " + button1.Content;
if (selected_button.Content == button1.Content)
{
button1.Visibility = Visibility.Collapsed;
selected_button.Visibility = Visibility.Collapsed;
points += 3;
}
else
{
points -= 1;
selected_button.Background = new SolidColorBrush(Colors.White);
}
selected_button = null;
//PageTitle.Text = "" + points;
}
else
{
selected_button = button1;
selected_button.Background = new SolidColorBrush(Colors.Green);
}
}
private void button2_Click(object sender, RoutedEventArgs e)
{
if (selected_button != null)
{
PageTitle.Text = "" + selected_button.Content + " " + button2.Content;
if (selected_button.Content == button2.Content)
{
button2.Visibility = Visibility.Collapsed;
selected_button.Visibility = Visibility.Collapsed;
points += 3;
}
else
{
points -= 1;
selected_button.Background = new SolidColorBrush(Colors.White);
}
selected_button = null;
//PageTitle.Text = "" + points;
}
else
{
selected_button = button2;
selected_button.Background = new SolidColorBrush(Colors.Green);
}
}
private void button11_Click(object sender, RoutedEventArgs e)
{
button11.Visibility = Visibility.Collapsed;
}
}
Please help :)