I’m new to Winforms. I’m using VS2022 and .NET 6 to create a Winforms app.
I created two forms (loginForm and MainForm). I’m trying to use the loginForm to protect data in MainForm. When user logs in, the loginForm should be hidden and show MainForm, so user can perform some actions.
When user finishes his actions, he should click logout, which shows the loginForm again, and hides the MainForm. Please help
5
You could try the example below.
I tested the following steps and it works.
click loginin -> show MainForm -> Click Hide MainForm -> show LoginForm->click login out -> then click loginin again -> show previously-hidden MainForm
internal static class Program
{
private static Form1 mainForm;
private static LoginForm loginForm;
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
mainForm = new Form1();
loginForm = new LoginForm();
loginForm.Login += LoginForm_Login;
loginForm.Logout += LoginForm_Logout;
loginForm.Show();
mainForm.Invisible += MainForm_FormInvisible;
Application.Run();
}
private static void MainForm_FormInvisible(object sender, EventArgs e)
{
mainForm.Hide();
loginForm.Show();
}
private static void LoginForm_Login(object sender, EventArgs e)
{
loginForm.Hide();
if (mainForm.IsDisposed)
{
mainForm = new Form1();
}
mainForm.Show();
}
private static void LoginForm_Logout(object sender, EventArgs e)
{
mainForm.Hide();
loginForm.Show();
}
}
LoginForm(loginbutton and logout button):
public partial class LoginForm : Form
{
public event EventHandler Login;
public event EventHandler Logout;
public LoginForm()
{
InitializeComponent();
}
private void OnLogin()
{
Login?.Invoke(this, EventArgs.Empty);
}
private void OnLogout()
{
Logout?.Invoke(this, EventArgs.Empty);
}
private void btnLogin_Click(object sender, EventArgs e)
{
OnLogin();
}
private void btnLogout_Click(object sender, EventArgs e)
{
OnLogout();
}
//exit button
private void button3_Click(object sender, EventArgs e)
{
Application.Exit();
}
}
MainForm((textbox and Hide button)):
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public event EventHandler Invisible;
private void button1_Click(object sender, EventArgs e)
{
OnHide();
}
private void OnHide()
{
Invisible?.Invoke(this, EventArgs.Empty);
}
}
3
You can try this:
[STAThread]
static void Main()
{
ApplicationConfiguration.Initialize();
while (true)
{
var dlg = new LoginForm();
if (dlg.ShowDialog() == DialogResult.OK)
{
Application.Run(new MainForm());
}
else if (dlg.ShowDialog() == DialogResult.Abort)
{
break;
}
}
}
and in LoginForm, provide two results
for success login: this.DialogResult=DiaglogResult.OK;
for exiting application: this.DialogResult=DiaglogResult.Abort;
1
Your code seems almost correct for switching between two Windows Forms in C#. However, there’s a mistake in the Form2 class where you’re creating an instance of Form1 instead of Form2 when switching back to Form1.
Here’s the corrected version of your code:
namespace SwitchBetweenWinfomToWinfomApp
{
internal static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
// To customize application configuration such as set high DPI settings or default font,
// see https://aka.ms/applicationconfiguration.
ApplicationConfiguration.Initialize();
Application.Run(new Form1());
}
}
}
namespace SwitchBetweenWinfomToWinfomApp
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void btnSwitchToForm2_Click(object sender, EventArgs e)
{
// Create an instance of Form2
Form2 form2 = new Form2();
// Show Form2
form2.Show();
// Hide the current form (Form1)
this.Hide();
}
}
}
namespace SwitchBetweenWinfomToWinfomApp
{
public partial class Form2 : Form
{
public Form2()
{
InitializeComponent();
}
private void btnSwitchToForm1_Click(object sender, EventArgs e)
{
// Create an instance of Form1
Form1 form1 = new Form1();
// Show Form1
form1.Show();
// Hide the current form (Form2)
this.Hide();
}
}
}
2