Loop C#中的父窗体和子窗体

Question

I am trying to create a login for my tool and have sorted that but when they press login(Child form) the program loops and asks the user to login again. I notice when I press the 'Exit' button it then loads the Parent form fine but I dont want that. I want my users to press login and then go right to the Parent form. To open the child form before the parent form inside of Form1_Load I have this:

        Login Log = new Login();
        Log.ShowDialog();

Inside the 'Login' button on the child form I have this:

        this.Hide();
        Form1 Main = new Form1();
        Main.Show();

Answer 1

The best way to handle this would be to handle the login BEFORE your form starts (eg in the Program.cs but after the application initialization). Insert a variable into your login form (Eg a bool that shows if they have passed your authorization test) and check after the form has closed to see what the status of authorization is. If the flag is set to false then you can do a return or Application.Exit() and the user will never see the main form.

static class Program
{
    /// <summary>
    /// The main entry point for the application.
    /// </summary>
    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        SomeLoginForm Login = new SomeLoginForm();
        Login.ShowDialog();
        if (!Login.HasPassedAuthorization)
        {
            MessageBox.Show("Sorry you failed to pass the test! I'm kicking you out now!");
            Application.Exit(); // or do a "return;"
        }

        Application.Run(new Form1());
    }
}


static class SomeLoginForm()
{
        internal bool HasPassedAuthorization;

}