C#/winform Timer class - need to hide one form, load another

kylewisdom2 · 2016-03-24T19:45:08.000Z

I have a program I wrote, everything works fine, it connects to a database, and to keep that database connection alive/secure, I have a timer that, after 60 minutes, goes back to the login screen for the program.

This was all working fine except one thing: I couldn’t get the timer to properly reset to 0, it would reset to 0 right away, even if I logged in or not, so if the timer hit 60, logged me out, and then I logged back in 57 minutes later, it would only have 3 minutes left on the timer.

So to fix this, I made the timer its own class instead of having it run right on one of the forms itself. I think this works as far as properly resetting the timer, because I have the timer reset to 0 when I click the login button, so all is well there.

HOWEVER, now my form hiding/showing is not working correctly.

I have tried hiding/showing the form from the Timer class, it keeps Form2 open and then opens Form1 on top of it. Then when I log back in, I have 2 Form2’s open.

Then I made a public void in Form2 that does this:

public void hideForm()
        {
            
            MessageBox.Show("Your session has timed out, please log in again");
            Form1 frm1 = new Form1();
            frm1.Show();
            this.Close();
        }

When the timer hits 60 minutes, it calls the hideForm() and it pops up the messagebox just fine, and it loads Form1 just fine.

But it still will not close the current form.

Does anyone know why this is happening? It worked fine before I separated he timer into its own class.

Any help is much appreciated, thanks!

lesleixu3531 · 2016-03-24T20:10:13.000Z

A timer is running in a thread other than main event thread (GUI thread), all manipulation of UI components should be done in main event thread. check out things like BeginInvoke to get familiar with C# GUI programing , which is very similar to Java Swing or other similar UI frame work.

williamsurritte3886 · 2016-03-24T23:49:07.000Z

I made a C# project that does what you want, but Spiceworks will not allow posting a ZIP file. PM me your email address if you want it.

Here is the gist of it:

 static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            GlobalVariables.Timer = new Timer();
            GlobalVariables.Timer.Interval = 60 * 1000; //Minute
            GlobalVariables.Timer.Interval = 60;//test one second
            GlobalVariables.Timer.Tick += new EventHandler(Timer_Tick);
            Application.Run(new frmLogin());
        }

        static void Timer_Tick(object sender, EventArgs e)
        {
            
            GlobalVariables.OpenTime++;
            if (GlobalVariables.OpenTime > 2)
            {
                ToggleForm();
            }
        }

        public static void ToggleForm()
        {
            //Form main = Application.OpenForms["Form1"];
            Form main = GlobalVariables.MainForm;
            if (main != null)
            {
                main.Hide();
            }
            Form login = Application.OpenForms["frmLogin"];
            if (login != null)
            {
                login.Show();
            }
            else
            {
                throw new Exception("Cant find login form");
            }
            GlobalVariables.Timer.Stop();
        }
    }

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace WinFormsTimerTest
{
    public static class GlobalVariables
    {
        public static System.Windows.Forms.Timer Timer
        {
            get;
            set;
        }

        public static int OpenTime
        {
            get;
            set;
        }

        public static System.Windows.Forms.Form MainForm
        {
            get;
            set;
        }

        
    }
}

kylewisdom2 · 2016-03-25T21:12:06.000Z

Okay, I ended up getting it. I took it out of the class and put it back in the form I was having everything work out of.

public void timer_Tick(object sender, EventArgs e)
        {
            logintimerCount += 1;
            intLabel.Text = logintimerCount.ToString();

            if (logintimerCount == 60)
            {

                MessageBox.Show("Your session has timed out, please log in again");
                myTimer.Stop();
                this.Hide();
                Form1 frm1 = new Form1();
                frm1.Show();
                
                
                

            }
        }

I did that for the timer and its ticks. Had it stop, then hide the form and load the login screen back up.

And then, during form load, it resets the counter to 0.

Played around with it enough to get my head on straight and get it all organized and put in the right places for it to work. Thanks everyone.