Disposing a form from parent form in C#?
Solution 1
If the two forms doesn't have a parent-dialog type of relationship, you might just want to hook into the Disposed event on the subform to get notified when it closes.
public partial class Form1 : Form
{
private Form2 _Form2;
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
if (_Form2 != null)
_Form2.Dispose();
_Form2 = new Form2();
_Form2.Disposed += delegate
{
_Form2.Dispose();
_Form2 = null;
};
_Form2.Show();
}
}
Then all you have to do in Form2 is simply to close it:
public partial class Form2 : Form
{
public Form2()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
Close();
}
}
Solution 2
MSDN docs on disposing of forms:
Dispose will be called automatically if the form is shown using the Show method. If another method such as ShowDialog is used, or the form is never shown at all, you must call Dispose yourself within your application.
On closing vs. disposing:
When a form is closed, all resources created within the object are closed and the form is disposed. You can prevent the closing of a form at run time by handling the Closing event and setting the Cancel property of the CancelEventArgs passed as a parameter to your event handler. If the form you are closing is the startup form of your application, your application ends.
The two conditions when a form is not disposed on Close is when (1) it is part of a multiple-document interface (MDI) application, and the form is not visible; and (2) you have displayed the form using ShowDialog. In these cases, you will need to call Dispose manually to mark all of the form's controls for garbage collection.
Solution 3
You don't need to explicitly call Dispose on the form, the garbage collector will do that for you.
If you want something specific to happen when Form2 "goes away", you can hook into it's form closing event.
EDIT :
On Form2, in the button click, try
this->Close();
That will close that instance of form2 (the form will disappear). If form1 still has a reference to form2, then form2 will not be picked up by the garbage collector, and the GC will not dispose of it.
If there is a reason for form1 to keep a reference to form2 ?
If so, form1 should handle from2's closing event, then form1 can release it's reference to form2 (set it to null).
Now the GC will pickup form2 as a candidate to be collected, it will (in possibly more than one step) call it's Dispose method and free up Form2's memory.
Solution 4
You are not really a reader right? Lot of answers here already.
Edit I want to close(dispose explicitely) form2 object which is created in form1 class when button on form2 is clicked. This edit is to give some more clarity.
If you use ShowDialog then form2 returns when you call close(). So in Form1:
private void button1_Click(object sender, System.EventArgs e)
{
Form2 oForm2 = new Form2();
oForm2.MyParentForm = this;
if (oForm2.ShowDialog() == DialogResult.OK)
{
oForm2.Dispose(); //or oForm2.Close() what you want
}
}
And then call Close() in form2.
M. Talha Bin Asif
Updated on June 27, 2022Comments
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M. Talha Bin Asif almost 2 years
I want to forecast the hourly rate of electricity using ARIMA. But, I won't be able to set the ts function correctly which results in no forecasting in Arima. My data has 24 entries per day. My aim is to predict 2022-05-01 18:00:00
Please help.
Here is code: start date: 07/01/2015 1:00, end date: 4/26/2022 15:00
data$Category <- as.Date(data$Category, format = "%m/%d/%Y") data <- data[order(data$Category), ] Y <- ts(data[,2], start = c(2015,07,01), frequency = 365*23) fit_arima <- auto.arima(Y, d=1, D=1, stepwise = FALSE, approximation = FALSE, trace = TRUE) print(summary(fit_arima)) checkresiduals(fit_arima)Data sample:
Category Series ID 07/01/2015 1:00 5244 07/01/2015 2:00 5152 07/01/2015 3:00 4948 07/01/2015 4:00 4485 07/01/2015 5:00 4231 07/01/2015 6:00 4158 07/01/2015 7:00 4324 07/01/2015 8:00 4686 07/01/2015 9:00 5060 07/01/2015 10:00 5347 07/01/2015 11:00 5504 07/01/2015 12:00 4368 07/01/2015 13:00 5440 07/01/2015 14:00 5280 07/01/2015 15:00 5227 07/01/2015 16:00 5195 07/01/2015 17:00 5195 07/01/2015 18:00 5252 07/01/2015 19:00 5200 07/01/2015 20:00 5228 07/01/2015 21:00 5244 07/01/2015 22:00 5277 07/01/2015 23:00 4517 08/01/2015 0:00 4629 08/01/2015 1:00 4996 08/01/2015 2:00 4910 08/01/2015 3:00 4655 08/01/2015 4:00 4230 08/01/2015 5:00 4000 08/01/2015 6:00 3943 08/01/2015 7:00 3907 08/01/2015 8:00 4830 08/01/2015 9:00 5298 08/01/2015 10:00 5638 08/01/2015 11:00 5874 08/01/2015 12:00 3910 08/01/2015 13:00 5864 08/01/2015 14:00 5943 08/01/2015 15:00 5893 08/01/2015 16:00 5744 08/01/2015 17:00 5573 08/01/2015 18:00 5392 08/01/2015 19:00 5290 08/01/2015 20:00 5231 08/01/2015 21:00 5152 08/01/2015 22:00 5063 08/01/2015 23:00 4125 -
Enjoy coding about 15 yearsya, but I want to dispose second form when button2 on form2 is clicked. how to do it?
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nightcoder almost 15 yearsIt seems like if you call Close() "when it is part of a multiple-document interface (MDI) application, and the form is not visible" it is disposed anyway. At least it is in my tests.
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Jrud over 14 yearsIf you hook into its close event, that creates an event handler you'll have to remove as well correct? sigh memory leaks are such a pain.
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Matthieu over 12 yearsThe second part of the answer is based on an old version of the framework. Anyone interested in the updated version of the Closing Event should look here : msdn.microsoft.com/en-us/library/…
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zumalifeguard almost 10 yearsWhy would you call _Form2.Dispose() inside of the delegate, if it's already disposing? -
M. Talha Bin Asif almost 2 yearsI tried with 24 but forecasting is not coming out to be right.
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alexrai93 almost 2 yearsCould you please explain better what "coming out to be right" means? Maybe include the model output and what your expectation is in terms of the forecast output and seasonal periods. Note that to forecast future periods you also need to use forecast(fit, h) and specify h as the number of periods which in your case is the number of hours.
