How to close one Winform upon opening another

Question

I have two Win forms in my project, one Login form, and the Main form. I have a button in Login form, which when clicked should open the Main form and close the current(Login) form.

I have tried this method

private void button1_Click(object sender, EventArgs e)
{
    Mainform frm = new Mainform();
                frm.Show();
                this.Hide();
}

But it only hides the current form. So even after I close the Main form, I have to manually stop debugging by pressing Shift + F5.

Then I have tried this following code

private void button1_Click(object sender, EventArgs e)
{
    Mainform frm = new Mainform();
                frm.Show();
                this.Close();
}

But now, when I click the button, the Mainform opens and within a second, both the forms are closed, and the program stops debugging.

How do I correctly open Mainform from Login form and I don't have to stop debugging ,manually ?

What kind of forms are you using? It is definitely not ASP.NET. WPF or Winforms? — keiv.fly, Jul 24 '16 at 19:24

Mostafiz · Accepted Answer · 2016-07-24T19:37:47.377

0

You can achieve this way

private void button1_Click(object sender, EventArgs e)
  {
     Mainform frm = new Mainform();
     frm.Show();

     this.ShowInTaskbar = false;
     this.WindowState = FormWindowState.Minimized;
  }

and in another place you can show login form again

private void button1_Click(object sender, EventArgs e)
  {
     this.ShowInTaskbar = true;
     this.WindowState = FormWindowState.Normal;
  }

edited Jul 24 '16 at 19:37

answered Jul 24 '16 at 19:29

Mostafiz

7,243
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Tried it just now. When I close the Mainform, the Login form appears again, and after closing the Login form, I have to manually stop debugging it. – Akeel.F Jul 24 '16 at 19:32
show some more details code, because there is no cause for login form come again – Mostafiz Jul 24 '16 at 19:35
and in mainform exit method you can use `Environment.Exit(0)` then you don't have to manually stop debugginh – Mostafiz Jul 24 '16 at 19:36
Use `Environment.Exit(0)` in MainForm exit method then everything will be close and you don't have to stop debugging manually – Mostafiz Jul 24 '16 at 19:39
great, happy coding :) – Mostafiz Jul 24 '16 at 19:41

score 0 · Answer 2 · answered Jul 24 '16 at 19:37

Your problem is that you host Form2 inside Form1.

As it seems, your application begins with Form1, and in it you then load Form2, now you close Form1 and expect Form2 to stay alive when you just killed its host.

A better approach would be to initialize your application with a different form, or static class preferred, which will "last" during the lifetime of your application.

this is exactly why you get a class named Program.cs added to your solution, when you start a new Windows Form project.

score 0 · Answer 3 · edited May 23 '17 at 12:32

0

As @polisha989 said, you can host MainForm in Program.cs if you want terminate application when MainForm is closed or eventually reopen Loginform there.

2nd optoin is to pass reference of LoginForm to MainForm and reopen LoginForm while MainForm is closing.

3rd option is to call Application.Exit() while MainForm is closing. (find more here How to properly exit a C# application?

edited May 23 '17 at 12:32

Community

1
1

answered Jul 24 '16 at 19:51

David Pivovar

115
1
10

How to close one Winform upon opening another

3 Answers3