Question

Please can someone tell me the technique that would be used, for the following scenario.

I would like to authenticate users, before I allow my code to perform another action.

I have a method that opens a new window that contains my authentication form (username and password).

    private bool userLogin()
    {
        Window loginInterface = new Window()
        {
            Title = "Please Login",
            Content = new login(),
            Height = 282,
            Width = 300,
            ResizeMode = ResizeMode.NoResize,
            WindowStartupLocation = WindowStartupLocation.CenterOwner

        };

        loginInterface.Owner = this;

        loginInterface.ShowDialog();

        return true;

    }

I’m calling this method like so, on button click:

    private void perform_action(object sender, RoutedEventArgs e)
    {
        if (!userLogin())
        {
            // Failed login, do nothing
        }
        else
        {
            // Authentication successful, perform action
            delete_item();
        }
    }

The window opens fine, but how can I now make my method return true or false based on the what the user does on the opened form?

So when the user clicks the login button named login_button, my code already validates the credentials, but I need the ‘bool’ value sent back.

Can I make my first window almost wait for an action to be performed on another window and get the response back?

Answer 1

The Window.ShowDialog() method actually already returns a bool?. This can be set at any point from within the Window by setting (for example) this.DialogResult = true. You can then close the window and access the value from the calling code.

To close the window with a result:

this.DialogResult = true;

…and then to use that result in the calling code:

var myWindow = /*create window*/;
var result = myWindow.ShowDialog();
if (result == true)
{
     //...
}