C# Winform The process still on Windows Task list manager after close programme

Question

why The process still on Windows Task list manager after close programme ?

i use login Form.cs

 [STAThread]
        static void Main()
        {
             


        

Answer 1

In winforms process will be killed, when main application form is closed. Main application form is one specified in Application.Run call. In your case it is Login form:

Application.Run(new Login());

To close form you should call Close method. When you call Hide or set Visibility to false, form stays in memory. It just becomes hidden from user.

So, to achieve desired functionality you should change main application form to Main_Usr:

static void Main()
{
    Application.EnableVisualStyles();
    Application.SetCompatibleTextRenderingDefault(false);
    Application.Run(new Main_Usr()); // change main form
}

Then subscribe to Load event of Main_User form. And in the event handler do following:

private void Main_User_Load(object sender, EventArgs e)
{
    using (var loginForm = new Login())
    {
        Hide(); // hide main form

        if (loginForm.ShowDialog() != System.Windows.Forms.DialogResult.OK)
        {
            Close(); // close main form and kill process
            return;
        }

        Show(); // show main form if user logged in successfully 
    }
}

UPDATE: You can do this all in Main method, like this way

static void Main()
{
    Application.EnableVisualStyles();
    Application.SetCompatibleTextRenderingDefault(false);
    using(var loginForm = new Login())
         if (loginForm.ShowDialog() != System.Windows.Forms.DialogResult.OK)
             return;
    Application.Run(new Main_Usr()); // change main form
}

but usually I don't hide main form and show it below login form. So, in this case you should use Load event handler. It's up to you.

BTW there is no masterpages and pages in winforms. This all is for ASP.NET. Here you have forms :) Also consider naming like LoginForm, MainForm etc.