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call an event from another event in c#

I have a question when programing in c#. I want to call an event from another event like this.
private void button1_Click(object sender, EventArgs e)
{
Form2 formulario = new Form2();
formulario.ShowDialog();
// here i call an event from the second form. that event is radiobutton_checkedchange
formulario.radioButton1_CheckedChanged(sender, e);
The problem is that i look everyware how to solve this problem... They said me that an event is like a method but i think is not the same, because when i call that event like a method it looks like i call it just once. The event dont recognize the checked change.
am I wrong ? is this posible in c#. Thanks to all, i'm new in programing with events. And sorry for my bad english

First, radioButton1_CheckedChanged is not an event, it is probably an event handler. In the end, it is still a method like all others.
You shouldn't directly call the event handler of an event, just create another method and what the call there. Put this in your Form2:
private void radioButton1_CheckedChanged(object sender, EventArgs e)
{ // private, only accessible from the class itself
this.SetState();
}
public void SetState()
{ // public, accessible from anywhere
// put your original code from radioButton1_CheckedChanged here
}
In that way, you don't have to call event specific code, but you can write that away in a separate method, which is easier to use and clearer in its purpose.
If both forms share the same data object / view model, you can set the value from there. That would be better from a OOP perspective. Look into MVVM or MVC for good design patterns to do so.

It sounds like you have logic in radioButton1_CheckedChanged that you also want to call when the button is clicked. If that's the case, then move the common logic to a new method and call it from both places.
If you want to change the checked status of radioButton1 then just change its status. Event hnadlers respond to UI changes, they do not generate them.

C# windows forms handle click spam [duplicate]

This question already has answers here:
Is it possible to avoid multiple button clicks on a Winform?
(3 answers)
Closed 2 years ago.
I have an app with many user controls and many buttons on each, each button has an OnClick event which does some important stuff and then sends to a new user control.
The problem comes when the user clicks really fast multiple times, the event code gets executed more than once before exitting to a new user control, causing problems.
My current solution is to disable the button on the very first line of the event handler, but doing this to every window and handler would be troublesome, what can I do?
EDIT: Would it be a good solution to derive from Button, and override the OnClick event so it always does a check for a "working" variable, and if it is true, it doesnt start the event ? Something like:
public class MyButton : Button
{
private static bool isWorking = false;
protected override void OnClick(EventArgs e)
{
if (!isWorking)
{
isWorking = true;
base.OnClick(e);
isWorking = false;
}
//Else do nothing
}
}

You can use some timeStamp to delay between 2 clicks:
DateTime timeStamp;
//this will handle the clicks with the allowed interval being 0.5 second
//Note that a tick is equal to 1/10,000,000 of second.
private void click_Handler(object sender, EventArgs e) {
if ((DateTime.Now - timeStamp).Ticks < 5000000) return;
timeStamp = DateTime.Now;
//your code goes here ....
}

If you want all buttons to wait until one button's work is done, add a bool isProcessing variable to your form. Wrap the work of each button inside an if (!isProcessing), and set that flag to true in the first line inside the if statement. Then don't forget to set it back to false right before you exit the if.
I'm assuming you're doing all of this asynchronously, since if it's all in the same thread, the form will lock while it's processing the work. This will solve your issue though.

Disabling controls while sensitive operation is on-going is a typical solution that I always apply.
But since there can be quite a few controls on one screen that are affected by some click or change in UI, I typically design forms to have a specialized method which walks through all the affected controls and disables/enables them accordingly.
Something like this:
void EnableControls(bool enable)
{
foreach (Control ctl in this.Controls)
ctl.Enabled = enable;
}
Similarly, you could group controls into related buckets, so to disable/enable only one of them etc. Depends on your precise needs.
There is an alternative solution to use timer - disable the button, but enable it after 1 sec. This prevents nervous users from clicking multiple times if that would cause damage to data (i.e. each click is treated as a new operation).

I would call the same function from every button and then perform the specific task:
private void Button_Click(object sender, EventAgrs e)
{
Button btn = sender;
btn.disable = true;
switch (btn.AccessibleName)
// call specific function for the particular button or do it all here
}

I'm not sure if this would even work, but just an idea...
You could try with aspect oriented approach (with the help of Postsharp for example):
Create two aspects, one for method entry and one for method exit. In the method entry mark the current method as 'processing' (add the method name to a hash set for example). In the method exit mark the method as 'not processing' (remove it from the hash set). Then in the method entry check if the method is processing and if it is, then cancel the method (like this: https://stackoverflow.com/a/2437794/113858)
Mark all of your event handlers with this aspect.

Assign Form1_Closing method to Form Closing Event

I have the following method defined to be called when a form closes
private void TimeKeeper_Closing(object sender, EventArgs e)
However, it doesn't show up in the list when I try to assign it in the Events section of the Form properties. Is there something I need to do to get it to show up there?
EDIT: Sorry, originally posted the wrong method...

The Closing event is obsolete, it dates from .NET 1.x. Microsoft goofed that one pretty badly and it was replaced in .NET 2.0 with the FormClosing event. Which tells you a lot more about why the form is getting closed. The e.CloseReason is very important, you don't want to prevent Windows from shutting down.
Which is why you can't find it, you are not supposed to use it anymore. Note how the answer you accepted just stops your program from compiling. You probably discovered the FormClosing event by yourself.
Might as well go whole-hog and point out how silly it is for a class to listen to its own events. Events are meant for other code. They work pretty well in the designer, that's why you end up writing code like this. But the sane thing to do is to just override the method:
protected override void OnFormClosing(FormClosingEventArgs e) {
if (e.CloseReason == CloseReason.UserClosing) {
// Some code that might set e.Cancel = true
//...
}
base.OnFormClosing(e);
}
Which has many advantages, beyond the typical lossage of forgetting to subscribe the event with the designer, a derived class can simple alter the decision being made here by setting e.Cancel back to true.

You have to change EventArgs to FormClosingEventArgs
private void TimeKeeper_Closing(object sender, FormClosingEventArgs e)

How to close a form in UserControl

I created a UserControl with the buttons Save, Close and Cancel. I want to close the form without saving on the Cancel button, prompt a message to save on the Close button and Save without closing on the Save button. Normally, I would have used this.Close() on the Cancel button, but the UserControl doesn't have such an option. So I guess I have to set a property for that.
Scrolling down the "Questions that may already have your answer" section, I came across this question: How to close a ChildWindow from an UserControl button loaded inside it? I used the following C# code:
private void btnCancel_Click(object sender, EventArgs e)
{
ProjectInfo infoScreen = (ProjectInfo)this.Parent;
infoScreen.Close();
}
This does the job for one screen, but I wonder if I have to apply this code for all the screen I have? I think there should be a more efficient way. So my question is: Do I need to apply this code for every form I have, or is there another (more efficient) way?

you can use
((Form)this.TopLevelControl).Close();

you can use the FindForm method available for any control:
private void btnCancel_Click(object sender, EventArgs e)
{
Form tmp = this.FindForm();
tmp.Close();
tmp.Dispose();
}
Do not forget to Dispose the form to release resources.
Hope this helps.

You also can close one form in any part of the code using a remote thread:
MyNamespace.MyForm FormThread = (MyNamespace.MyForm)Application.OpenForms["MyForm"];
FormThread.Close();

I found the simple answer :) I all ready thought of something like that.
To close a WinForm in a ButtonClicked Event inside a UserControl use the following code:
private void btnCancel_Click(object sender, EventArgs e)
{
Form someForm = (Form)this.Parent;
someForm.Close();
}

How do you PerformClick(); for a button on a different tab?

I'm using Visual c# express 2010, I have 3 tabs and on the first tab there is a button that exits the program. I'm trying to call that button click on the 2nd and 3rd tab with
btnExit.PerformClick();
but since it isn't visible nothing happens. How would I call the invisible button click?
any help would be appreciated
EDIT:
Thanks for the replies, the two answers work great but I found a way that I think is easier and better.
instead of systematically changing tabs or calling a whole different method, I did this
btnExit_Click(sender, e);
I can put that in any other button click and it works great, very simple to.

I think it's better to create a method that actually has the code to exit the program, and call that method from btnExit click event and also other buttons click event, than PerformClick of the exit button.
void ExitApplication()
{
// code to exit the application
}
protected void btnExit_Click(object sender, EventArgs e)
{
ExitApplication();
}
protected void ButtonInOtherTab_Click(object sender, EventArgs e)
{
ExitApplication();
}
This way it's easier to read and understand.

myTabs.SelectedTab = specificTab;
btnExit.PerformClick();