Develop Reference

When CheckBox is unchecked make it unable for specific time C#

I am working on antivirus program and on real-time protection panel I want checkbox when for example "Malware protection" checkbox is unchecked to make it not enable for like 15 minutes and after that time it is enabled again so it prevents spam.
If somebody can help me it would be great
I tried with Thread.Sleep() but it stops whole application, and I tried with timer but I think I did it wrong.
This is code for timer
private void checkBox1_CheckStateChanged(object sender, EventArgs e)
{
if (this.checkBox1.Checked)
{
this.checkBox1.Text = "On";
// these two pictureboxes are for "You are (not) protected"
// picture
picturebox1.Show();
pictureBox5.Hide();
timer1.Stop();
}
else
{
this.checkBox1.Text = "Off";
// this is the problem
timer1.Start();
this.checkBox1.Enabled = true;
pictureBox1.Hide();
pictureBox5.Show();
}
}
private void timer1_Tick(object sender, EventArgs e)
{
this.checkBox1.Enabled = false;
}

Short Answer
From the code you posted, it really only appears that you need to change the code to disable the checkbox in the CheckChanged event and enable it in the timer1_Tick event (and also Stop the timer in the Tick event).
Full Answer
Winforms has a Timer control that you can use for this. After you drop a Timer onto the designer, set the Interval property to the number of milliseconds you want to wait before enabling the checkbox (1 second is 1000 milliseconds, so 15 minutes is 15min * 60sec/min * 1000ms/sec, or 900,000 ms). Then double-click it to create the Tick event handler (or add one in your Form_Load event as I've done below).
Next, in the CheckChanged event, if the checkbox is not checked, disable the checkbox and start the timer.
Then, in the Tick event, simply enable the checkbox (remember, this event is triggered after Interval milliseconds have passed) and stop the timer.
For example:
private void Form1_Load(object sender, EventArgs e)
{
// These could also be done in through designer & property window instead
timer1.Tick += timer1_Tick; // Hook up the Tick event
timer1.Interval = (int) TimeSpan.FromMinutes(15).TotalMilliseconds; // Set the Interval
}
private void timer1_Tick(object sender, EventArgs e)
{
// When the Interval amount of time has elapsed, enable the checkbox and stop the timer
checkBox1.Enabled = true;
timer1.Stop();
}
private void checkBox1_CheckedChanged(object sender, EventArgs e)
{
if (!checkBox1.Checked)
{
// When the checkbox is unchecked, disable it and start the timer
checkBox1.Enabled = false;
timer1.Start();
}
}

This can be done without using Timer explicitly. Instead use asynchronous Task.Delay, which will simplify the code and make it easy to understand actual/domain intentions.
// Create extension method for better readability
public class ControlExtensions
{
public static Task DisableForSeconds(int seconds)
{
control.Enabled = false;
await Task.Delay(seconds * 1000);
control.Enabled = true;
}
}
private void checkBox1_CheckStateChanged(object sender, EventArgs e)
{
var checkbox = (CheckBox)sender;
if (checkbox.Checked)
{
checkbox.Text = "On";
picturebox1.Show();
pictureBox5.Hide();
}
else
{
checkbox.Text = "Off";
checkbox.DisableForSeconds(15 * 60);
pictureBox1.Hide();
pictureBox5.Show();
}
}

You could diseable and enable it with task.Delay(). ContinueWith(). This creates a new thread that fires after the delay is done. You need to make it thread safe, winforms isnt thread safe on its own

You should use Timer.SynchronizationObject

Run Form1 for 5 times than close Form1, restart

I'd like to add a loop to:
private void button5_Click(object sender, EventArgs e)
{
}
This will run Form1 for 5 times with 3 second delay than close all, than do it again.
I'm using this code to open them manually;
Form1 form = new Form1();
form.Show();
And I need to stop the loop with;
private void button6_Click(object sender, EventArgs e)
{
}
I'm new to coding and if you can explain it with code examples I would be grateful.

Im not sure why you ever want this. But here is the way.
You need a Timer with interval of 3000 milliseconds (3 seconds) that will fire an Event at every interval. Inside that Event you will Open up forms and will close all the forms if 5 forms are opened.
Timer _timer = new Timer(); // This is the timer
List<Form> forms = new List<Form>(); // This will hold list of forms.
private void button1_Click(object sender, EventArgs e)
{
_timer.Enabled = !_timer.Enabled; // toggle event with this button.
}
private void Form1_Load(object sender, EventArgs e) // initialize timer with form load event
{
_timer.Interval = 3000; // set interval
_timer.Tick += OpenUpForm; // set event
}
private void OpenUpForm(object sender, EventArgs e) // this is the event that should be fired every 3 seconds
{
if (forms.Count == 5) // if forms reached 5 attempt to close all
{
// ForEach will perform this actions for every form in forms list
forms.ForEach(f =>
{
f.Close(); // close form
f.Dispose(); // free resources
});
forms.Clear(); // clear the list
return;
}
forms.Add(new Form()); // add a new form to list
forms.Last().Show(); // show the form
}
Note that this will just open empty forms. If you want to open specific form you should create a 5 copy of that and put them inside list. and just open and close them.

Trying to change output for a timer in a form in c#

I need to make a form in C# have a timer and have a label that will have be the display of the timer. The label will need to be a generic label at first saying it is a counter, but when the timer starts it needs to display the count. Currently I have the display as a number up down but, it needs to be the control that can tweak the count, which it does. It just can't be the sole counter.
Here is my assignment:
Create a Windows Application. In the main form, create a label named “lTickCount”.
Create a timer named “tPeriodic”, and a numerical control of your own choosing.
Each time the timer “ticks” increment an integer, display the integer value as a string in
lTickCount. Use the numerical control to change the update rate of the timer
interactively.
I think I have done everything correctly except for the bold part. To finish I tried to make a string in both the label and the counter. I know I shouldn't have in both, I just wanted to show you the two things I've tried to help get better feedback:
namespace WindowsFormsApplication3
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
this.Text = "AAAAAAAA AAAAAAAA ########";
}
private void checkBox1_CheckedChanged(object sender, EventArgs e)
{
if (checkBox1.Checked)
{
TickCounter.Text = "The timer has started";
tPeriodic.Enabled = true;
}
else
{
TickCounter.Text = "The timer has ended";
tPeriodic.Enabled = false;
}
}
private void TickCounter_ValueChanged(object sender, EventArgs e)
{
TickCounter.Text = TickCounter.Value.ToString();
}
private void tPeriodic_Tick(object sender, EventArgs e)
{
TickCounter.Value += 1;
}
private void label1_Click(object sender, EventArgs e)
{
TickCounter.Text = TickCounter.Value.ToString();
}
private void Form1_Load(object sender, EventArgs e)
{
}
}
}
Can someone help me figure out what I'm doing wrong and point me in the right way?

If you are going to try to add to a string (A label value) you need to convert it to an Integer first.
A couple ways to do this:
TextCount.Text = (Convert.ToInt32(TextCount.Text) + 1).ToString();
is one way, of course you could still use your += or any other math syntax for basic addition of +1.
You can also use tryParse, and in fact this should probably be used to verify you have an integer in the first place:
int count;
if (int.TryParse(TextCount.Text, out count))
{
count++;
TextCount.Text = count.ToString();
}

int count;
int tmrInterval = 1000; //1 sec
private void tPeriodic_Tick(object sender, EventArgs e)
{
count++;
lTickCount.Text = count.ToString();
}
private void TickCounter_ValueChanged(object sender, EventArgs e)
{
if (TickCounter.Value == 0)
{
return; // or stop the timer
}
tPeriodic.Interval = TickCounter.Value * tmrInterval;
}
tPeriodic.Interval is the time till next tick in milliseconds.
You are updating the timer interval according to tmrInterval and the value of the numeric control. You can change the interval or the formula i wrote to your own.
valter

Ok I found that:
tPeriodic.Interval = 1000 / Convert.ToInt32(TickCounter.Value * TickCounter.Value);
seemed to work in the numericupdown class.
Thanks for the help.

Can not click button when a method running

private void AddMyScrollEventHandlers()
{
VScrollBar vScrollBar1 = new VScrollBar();
}
private void button1_Click(object sender, EventArgs e)
{
while (true)
{
if (vScrollBar1.Value + 1 < vScrollBar1.Maximum)
{
vScrollBar1.Value = vScrollBar1.Value + 1;
label1.Text = vScrollBar1.Value.ToString();
}
else
{
break;
}
System.Threading.Thread.Sleep(200);
}
}
private void button2_Click(object sender, EventArgs e)
{
// vScrollBar1.Scroll
}
I am new in C#. I was working on scroll. What I wanted here is, if anyone click button1 then scroll automatically move to the end and I wanted to show gradual value in label1. Also when someone click button2 scrolling stop.
Now the problem is label1 do not show gradual change in value. It shows value once when the scrolling stop.
Also when scrolling continue i,e when while loop is working I can not click on button2. Actually I can not click on the form even.
Someone please give me some idea how to do this.

This happens because the thread that is performing the task is busy, and it's the same thread that updates the UI. You can use a multithreading solution. Take a look at
BackgroundWorker

All the UI events run in the main thread of the application, so the application can only process one event at a time. When the application is processing an event, no other event will be processed.
Since you are doing a UI related work periodically, the best option is to use the Timer class:
Drop Timer from the toolbox into the form.
In the properties window, set the interval to 200.
Double click the timer object to create the Tick event handler.
Put this code in the newly created timer1_Tick method:
if (vScrollBar1.Value + 1 < vScrollBar1.Maximum)
{
vScrollBar1.Value = vScrollBar1.Value + 1;
label1.Text = vScrollBar1.Value.ToString();
}
else
{
timer1.Stop();
}
Change your methods as below:
private void AddMyScrollEventHandlers()
{
timer1.Start();
}
private void button2_Click(object sender, EventArgs e)
{
timer1.Stop();
}
Now you're done.

I would recommend using BackgroundWorker control, as suggested by Agustin Meriles. However, one more important thing to note is that You should use Control.Invoke(...) method to update controls from another thread.
I've modified Your code, tested it in a sample application and it seems to work correctly.
First, add a new BackgroundWorker control to Your form and assign backgroundWorker1_DoWork to its DoWork event.
Then, You can use the code below:
private void button1_Click(object sender, EventArgs e)
{
//code from here is moved to BackgroundWorker control
backgroundWorker1.RunWorkerAsync();
}
private void button2_Click(object sender, EventArgs e)
{
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
//while (true)
//the condition directly in the while looks more clear to me
while (vScrollBar1.Value + 1 < vScrollBar1.Maximum)
{
//update controls using Invoke method and anonymous functions
vScrollBar1.Invoke((MethodInvoker)delegate() { vScrollBar1.Value += 1; });
label1.Invoke((MethodInvoker)delegate() { label1.Text = vScrollBar1.Value.ToString(); });
//when called inside BackgroundWorker, this sleeps the background thread,
//so UI should be responsive now
System.Threading.Thread.Sleep(200);
}
}
If You have any problems when using this code, please let me know.
Update
As mentioned in the comments, You could also use ProgressChanged event of the BackgroundWorker. It requires some more changes in the code, but is more suitable in this case. You can find some information about it here: http://msdn.microsoft.com/en-us/library/system.componentmodel.backgroundworker.progresschanged.aspx.
If You are not going to add any other code with more processing in the while loop, You can also use Timer control, as suggested by MD.Unicorn in his answer.

c# loop every minute - where to put the code?

Currently I'm moving from java to c# and I'm full of crazy questions.
I'm trying new things on a windows form application and now,I would like to create a loop wich is executing a code every 1 minute,the problem is that I have no idea where to put this code.
For example,the form structure is like:
using System;
namespace Tray_Icon
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
notifyIcon1.ShowBalloonTip(5000);
}
private void notifyIcon1_BalloonTipClicked(object sender, EventArgs e)
{
label1.Text = "Baloon clicked!";
}
private void notifyIcon1_BalloonTipClosed(object sender, EventArgs e)
{
label1.Text = "baloon closed!";
}
private void contextMenuStrip1_Opening(object sender, CancelEventArgs e)
{
}
private void option1ToolStripMenuItem_Click(object sender, EventArgs e)
{
//some code here
}
private void option2ToolStripMenuItem_Click(object sender, EventArgs e)
{
//some code here
}
private void option3ToolStripMenuItem_Click(object sender, EventArgs e)
{
label1.Text = "Option 3 clicked!";
}
private void notifyIcon1_MouseDoubleClick(object sender, MouseEventArgs e)
{
option1ToolStripMenuItem_Click(this, null);
}
private void closeToolStripMenuItem_Click(object sender, EventArgs e)
{
this.Close();
}
private void btnWrite_Click(object sender, EventArgs e)
{
//code here
}
}
}
Where should I put the loop code? :(
Thanks in advance for ANY replay!!!

Add a Timer to your form:
set its Interval property to 60000 (one minute in milliseconds) and Enabled to True:
and attach an event handler to the Timer.Tick event, e.g. by double-clicking the timer in the Forms designer:
private void timer1_Tick(object sender, EventArgs e)
{
// do something here. It will be executed every 60 seconds
}

You would have to add a timer, and set the interval to 1000 miliseconds, and in the OnTick event you add the code with your loop
Timer tmr = null;
private void StartTimer()
{
tmr = new Timer();
tmr.Interval = 1000;
tmr.Tick += new EventHandler<EventArgs>(tmr_Tick);
tmr.Enabled = true;
}
void tmr_Tick(object sender, EventArgs e)
{
// Code with your loop here
}

You can't put any loop code in here.
In your designer look for the Timer control. When you have that, configure it to run every minute and place your code in the Timer_Tick event.
Or create a timer manually in code and respond to the event :) But for starters, doing it by the designer is easier!

Drag a Timer component on the Form and doubleclick it. There you go with the code.
The Timer component runs in the main thread so you can modify UI components without worrying.
Alternatively You could create a System.Timers.Timer, which has it's own thread and has some advantages, but possible caveats when modifying UI components. See http://msdn.microsoft.com/en-us/library/system.timers.timer.aspx

Try to use Background Worker and put the code in the backgroundWorker.DoWork or use a Timer

Use System.Timers.Timer:
System.Timers.Timer aTimer;
{
aTimer = new System.Timers.Timer();
aTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
aTimer.Interval = 60000;
aTimer.Enabled = true;
}
private static void OnTimedEvent(object source, ElapsedEventArgs e)
{
Console.WriteLine("The Elapsed event was raised at {0}", e.SignalTime);
}
for using Timer see this tutorial: C# Timer

How you do it in Java platform?
I think Java should be the same with .net.
In fact, a form program is just normal program which contains a event dispatcher. The event dispatcher listen to the UI events and dispatch them to the event handlers. I think all the UI mode should like this, no matter Java or .net platform.
So generally speaking, you have 2 options:
Start the loop at beginning. In this case, you should insert your
code in the constructor of the Form.
Start the loop when user
click the button. In this case, you should insert your code in the
event handler function.
Yes, as others mentioned, you should use the timer. But this should after you know where your code should locate. You also can use a endless loop with a sleep call. But timer is a better solution.

Idea of timer is more better. But If you want to use threads. Then Follow this
Let me assume that You want to do it right from the start of program
You can write in body of function (event in fact) named Form1_Load as
Your actual code is just within while loop other code only to guide
I can guide if you don't know the use of threads in C#
bool button2Clicked = false;
private void Form1_Load(object sender, EventArgs e)
{
// A good Way to call Thread
System.Threading.Thread t1 = new System.Threading.Thread(delegate()
{
while (!button2Clicked)
{
// Do Any Stuff;
System.Threading.Thread.Sleep(60000); //60000 Millieconds=1M
}
});
t1.IsBackground = true; // With above statement Thread Will automatically
// be Aborted on Application Exit
t1.Start();
}