c# Shutdown a system after holding yes for 5 seconds - c#

I was wondering if anyone knows how to use a dialog box to create a hold down button event. Here is the scenerio:
a user would like to shutdown their system, but because it is critical that they confirm, that user must hold the button for 5 seconds before the action can be done.
I am trying to do it in a yes no scenario ie.
To confirm shutdown please hold "Yes" for 5 seconds.
Anyone done this before able to offer a little help/insight?

Try using a button's Mouse_Down & Mouse_Up event, and a timer (this assumes you're using WinForms).
private void button1_MouseDown(object sender, MouseEventArgs e)
{
if (this.timer1.Enabled == false)
{
this.timer1.Interval = 5000;
this.timer1.Enabled = true;
}
}
private void timer1_Tick(object sender, EventArgs e)
{
this.timer1.Enabled = false;
MessageBox.Show("Shutdown!");
}
private void button1_MouseUp(object sender, MouseEventArgs e)
{
timer1.Enabled = false;
}

You could capture the button press on 'mousedown', and start a 5-second timer. Once the timer completes, shutdown is initiated. If a 'mouseup' event happens, it could stop and reset the timer.

Sure, handle BOTH the mousedown event and the mouseup event. Start a timer on the mousedown and see how long it has run on the mouseup. Done!

You could do this any number of ways. The first that comes to my mind would be to spin off a thread that waits 5 seconds and is simply aborted if the user's mouse comes back up.
Thread shutdown;
private void button1_MouseDown(object sender, MouseEventArgs e)
{
shutdown = new Thread(()=>ShutDown());
shutdown.Start();
}
private void ShutDown()
{
Thread.Sleep(5000);
Console.Write("5 seconds has elapsed");
// Do something.
}
private void button1_MouseUp(object sender, MouseEventArgs e)
{
if (shutdown != null)
{
shutdown.Abort();
shutdown = null;
}
}
Low overhead and you're not adding additional supporting controls for something this simple.

Why bother when you can just use getAsyncKeyState()? Tell them to hold down 'y' for 5 seconds. You can find a reference here: http://www.pinvoke.net/default.aspx/user32.getasynckeystate
Or you can do it your way and start a timer on MouseDown, then on MouseUp, end the timer and then see if it's more or less than 5 seconds. http://msdn.microsoft.com/en-us/library/system.windows.forms.control.mousedown%28VS.71%29.aspx

You can use the Form.MouseDown events do detect that the user has pressed the mouse button. In the event handler, check to see if cursor is over the button or not (the event is passed in the coordinates of the cursor). You can then enable a timer which will tick in 5 seconds, and perform the shutdown when the timer ticks.

When the user first clicks YES, start a timer that repeatedly checks if the mouse location is inside of the button. After 5 seconds has elapsed, proceed with the shutdown. If the user moves the mouse out of the button, stop the timer.

private DateTime mouseDownTime;
private void Button_MouseDown(object sender, MouseButtonEventArgs e)
{
mouseDownTime = DateTime.Now;
}
private void Button_MouseUp(object sender, MouseButtonEventArgs e)
{
if (mouseDownTime.AddSeconds(5) < DateTime.Now)
MessageBox.Show("You held it for 5 seconds!");
}

You can set up a timer on the MouseDown event, and if the mouse capture changes (check the MouseCaptureChanged event) to false before the timer event fires, cancel the timer.

Related

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

NotifyIcon - prevent multiple database query

I have a NotifyIcon and I set balloon text with MouseMove event. The balloon text comes from a database. This results continuous database query.
private void notifyIcon1_MouseMove(object sender, MouseEventArgs e)
{
//database operations.......
}
How can I prevent this? I want to set balloon text once when mouse on NotifyIcon.
Use the BalloonTipShown event (https://msdn.microsoft.com/en-us/library/system.windows.forms.notifyicon.balloontipshown(v=vs.110).aspx)
The behaviour you are looking for matched that event alot better then the MouseMove event
Another approach would be to add a Timer to your Form and set its Interval to a delay like 1 second. This delay would be how often the user could hit the database. Setup a Flag that gets reset by the Timer and check it in your NotifyIcon event. Something like:
private bool AllowUpdate = true;
private void notifyIcon1_MouseMove(object sender, MouseEventArgs e)
{
if (AllowUpdate)
{
AllowUpdate = false; // don't allow updates until after delay
// ... hit the database ...
// ... update your text ...
timer1.Start(); // don't allow updates until after delay
}
}
private void timer1_Tick(object sender, EventArgs e)
{
// reset so it can be updated again
AllowUpdate = true;
timer1.Stop();
}

How to wait for a button to be clicked?

After a button is clicked in a Windows form application written in C#, how to wait for another button to be clicked? Meanwhile I am updating a datagridview dynamically by current information.
EDIT
After button1 is clicked, I want to repeatedly update a dataGridView with current information and when button2 is clicked I want to stop updating the dataGridView.
Use Timer Class.
public partial class Form1 : Form
{
System.Windows.Forms.Timer timer;
public Form1()
{
InitializeComponent();
//create it
timer = new Timer();
// set the interval, so it'll fire every 1 sec. (1000 ms)
timer.Interval = 1000;
// bind an event handler
timer.Tick += new EventHandler(timer_Tick);
//...
}
void timer_Tick(object sender, EventArgs e)
{
//do what you need
}
private void button1_Click(object sender, EventArgs e)
{
timer.Start(); //start the timer
// switch buttons
button1.Enabled = false;
button2.Enabled = true;
}
private void button2_Click(object sender, EventArgs e)
{
timer.Stop(); //stop the timer
// switch buttons back
button1.Enabled = true;
button2.Enabled = false;
}
From MSDN:
A Timer is used to raise an event at user-defined intervals. This
Windows timer is designed for a single-threaded environment where UI
threads are used to perform processing. It requires that the user code
have a UI message pump available and always operate from the same
thread, or marshal the call onto another thread.
When you use this timer, use the Tick event to perform a polling
operation or to display a splash screen for a specified period of
time. Whenever the Enabled property is set to true and the Interval
property is greater than zero, the Tick event is raised at intervals
based on the Interval property setting.
So you have button A and button B. When button A is pressed you want to wait for button B to be pressed, then do something special? Without more information the simplest way is something like this:
private void OnButtonAClicked(object sender, EventArgs e)
{
ButtonA.Enabled = false;
ButtonA.Click -= OnButtonAClicked;
ButtonB.Click += OnButtonBClicked;
ButtonB.Enabled = true;
}
private void OnButtonBClicked(object sender, EventArgs e)
{
ButtonB.Enabled = false;
ButtonB.Click -= OnButtonBClicked;
// Do something truly special here
ButtonA.Click += OnButtonAClicked;
ButtonA.Enabled = true;
}
This code will toggle(initial state; button A is enabled, button B is disabled), when button A is pressed, button B becomes enabled and processes events, etc.
Use the BackgroundWorker http://msdn.microsoft.com/en-us/library/system.componentmodel.backgroundworker.aspx
It doesn't freeze the UI, support ProgressBar, also it can be async. At the link you will see a good example with same functional that you want (start some task by click on one button and cancel it by click on another button).

How to catch event Mouse Hold on a control?

I want to catch the event that user clicks and holds mouse on a control in C#.
I have read on MSDN and I only see events Mouse Down, Mouse Up, ... but don't have Move Hold event.
You need to use mentinoed events with some timer between them.
Example:
MouseDown
Start Timer
MouseUp
Disable Timer
In case if user holds more then timer time - invoke your event handler, when mouseUp happend faster then timer elapsed - disable runned timer.
First, you should use stop watch to detect time you want.
using System.Diagnostics;
Second, define a global instance of stopwatch class.
Stopwatch s = new Stopwatch();
This is the first event you should use:
private void controlName_MouseDown(object sender, MouseEventArgs e)
{
s.Start();
}
This is the second event you should use:
private void controlName_MouseUp(object sender, MouseEventArgs e)
{
s.Stop();
//determine time you want . but take attention it's in millisecond
if (s.ElapsedMilliseconds <= 700 && s.ElapsedMilliseconds >= 200)
{
//you code here.
}
s.Reset();
}

Capture spacebar press to pause Timer C#

I have a windows form which is a countdown Timer. What is the best way for me to pause the timer by pressing the spacebar on the keyboard. I have three buttons on the form for start, pause and stop and res-set. However I also want to pause, restart on press off spacebar. I tried to add a fourth button and then made it hidden on the form and added the following code (changed the EventArgs to KeyEventArgs:
private void button1_Click(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Space)
// Pause the timer.
timer1.Enabled = false;
paused = true;
Start.Enabled = true;
Pause.Enabled = false;
}
However when i try to run this i get the error - No overload for 'button1_Click matches
delegate System.EventHandler
Is there something I have missed or a better way off doing this.
Any Help/Advice would be appreciated.
The Click event doesn't take a KeyEventArgs.
You're looking for the form's KeyPress event.

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