How can I prevent WPF Window from opening if I have an already opened window ?

Question

I have an opened window and I am using the .Show() method, I would like to prevent any other windows to be opened If I have an opened window. something else than ShowDialog().

Answer 1

Keep track of the number of open windows as you open them one way or another, .e.g.:

public class WindowService
{
    private const int MaxNumberOfOpenWindows = 1;
    private int _currentNumberOfOpenWindows = 0;

    public void OpenWindow()
    {
        if (_currentNumberOfOpenWindows != MaxNumberOfOpenWindows)
        {
            Window window = new Window();
            window.Closed += Window_Closed;
            window.Show();
            _currentNumberOfOpenWindows++;
        }
    }

    private void Window_Closed(object sender, EventArgs e)
    {
        Window window = (Window)sender;
        window.Closed -= Window_Closed;
        _currentNumberOfOpenWindows--;
    }
}