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Why is my dynamically added event handler not firing consistently

Hello i basically added datagridviews dynamically to my windows form application, and added cellClick event handlers dynamically by looping through all the datagridview control, however my event doesnt fire consistently, like when i click really fast it wont clear the selection sometimes. here is my code
void DGV_CellClick(Object sender, EventArgs e)
{
DataGridView dgv = (DataGridView)sender;
dgv.ClearSelection();
}
foreach(KeyValuePair<int,datagridview>entry in DGVCollection)
{
datagridview dgv = entry.value;
dgv.CellClick+= DGV_CellClick;
}

"however my event doesnt fire consistently, like when i click really fast it wont clear the selection sometimes. here is my code"
It's possible that the CellDoubleClick event get's fired instead of the CellClick event.
You could take a look at this link

C# WinForm DataGridView Filter pause

I have a VisualStudio generated DataSet.
I connected them into a DataGridView (width connected by VisualStudio).
I'm using a filter. For example:
xyBindingSource.Filter = "yx = 'tart'";
My problem:
If I change any value of yx column (from tart to anything else), the changed row will remove before a CellEndEdit event going to run.
And in a CellEndEdit event, the DataGridViewCellEventArgs will contains the correct row and column number.
But the row what is pointed by the event args is not that, what is edited, because the selected row is removed earlier.
What can I do?
Thanks for help:
Norbi

You can handle this by using the DataGridView.CurrentCellDirtyStateChanged Event. This can raise the DataGridView.CellValueChanged Event, if you do it like this:
void dataGridView1_CurrentCellDirtyStateChanged(object sender,
EventArgs e)
{
if (dataGridView1.IsCurrentCellDirty)
{
dataGridView1.CommitEdit(DataGridViewDataErrorContexts.Commit);
}
}
CommitEdit manually raises the DataGridView.CellValueChanged Event. You can reload your Filter Method inside this Event again. Give it a try.

Adding Events To WinForms?

I have a TextBox on a WinForm and I want to execute some code every time someone presses a key inside of that TextBox. I'm looking at the events properties menu, and see the KeyDown event, but don't know how to add code to it.

You need to add an event handler for that event. So in the properties menu, double-click on the field beside the KeyDown event and Visual Studio will create an event handler for you. It'll look something like this:
private void textBox1_KeyDown(object sender, KeyEventArgs e)
{
// enter your code here
}
You can also subscribe to events yourself without using the Properties window. For example, in the form's constructor:
textBox1.KeyDown += HandleTextBoxKeyDownEvent;
And then implement the event handler:
private void HandleTextBoxKeyDownEvent(object sender, KeyEventArgs e)
{
// enter your code here
}

These answers will have visual studio generate the event and bind it behind the scenes in the Designer.cs file.
If you want to know how to bind events yourself, it looks like this.
MyTextBox.KeyDown += new KeyEventHandler(MyKeyDownFunction)
private function MyKeyDownFunction(object sender, KeyEventArgs e) {
// your code
}
If done this way, the new KeyEventHandler() part is optional. You can also use lambdas to avoid boilerplate code.
MyTextBox.KeyDown += (s, e) => {
// s is the sender object, e is the args
}

Doubleclick the textfield next to it.

I assume you are in Visual Studio. One way would be to double click on the empty textbox on the right of the KeyDown event: VS will generate the code for you.

You need to add a handler to the event.
Double-click the KeyPress event in the textbox's Properties window to make Visual Studio generate an event handler in the code file.
You can then put any code you want to inside the event handler function. You can check which key was pressed by writing e.KeyCode.

Windows Forms: detect the change of the focused control

I'm implementing copy-paste in a Windows Forms application.
I need to enable/disable the bar-buttons for this two operations when the user changes the focused element in the application.
I can find the current focused control using something like this: http://www.syncfusion.com/FAQ/windowsforms/faq_c41c.aspx#q1021q, but how can I detect that the focused control has changed?

In your form load event handler you could also loop through all of the controls contained in the form and for each focusable control add an event handler for the Enter event:
private void Form1_Load(object sender, EventArgs e)
{
foreach (Control control in Controls)
{
control.Enter += ControlReceivedFocus;
}
}
void ControlReceivedFocus(object sender, EventArgs e)
{
Debug.WriteLine(sender + " received focus.");
}

My proposal is to use Application.Idle event.
Write logic that enables/disables your buttons in Application.Idle event.
Subscribe to Application.Idle event on form shown event
Check button availability on button click (so you never pass accidental click under heavy load)
Do not forget to remove Idle handler on form disposing (or closing), because this is static event
Using this technique you will always have correct buttons state, and you not need to worry about subscribing to many controls events to detect focus change. This is also light-weight approach, because Idle event is raised only when application is not busy.

I think you should add an event handler to the control (or if you have many of the same type, subclass it, and override the appropriate OnChange handler). This way you won't have to 'find' the focused control (it will be given as the sender parameter), and the event will only arise when the change actually happened.

To detect the focus on a control you can create this event:
void MyGotFocus(object sender, EventArgs e)
{
if (sender is TextBox)
{
//TODO YOUR OPERATION
//FOR EXAMPLE
(sender as TextBox).SelectAll();
}
}
and the next step is to associate the control and event by code:
myText1.GotFocus += MyGotFocus;
myText2.GotFocus += MyGotFocus;

Calling my own event code and custom event code in c#

I have made a WinForms application with a custom richtextbox control.
I am referring it as a Windows control (a dll file) in my project. In my program for the richtextbox I have written functionality inside it's textchanged event.
I want to do additional work only after the textchanged event is fired or in other ways once the text is added to the textbox. Something like I want to call a function foo() in the text_changedevent. It only calls foo and fails to process the underlying textchanged event.
Any way in C# I can make it process the internal textchanged event first, and then look into my text changed event?
think of the scenario I have written the code for mytextbox_textchanged
private void txt_code_TextChanged(object sender, EventArgs e)
{
//some code which will always be called whenever textchanged event occurs.
}
Now I inherit this control in my project say MyApp1. Here I have a label where I want to display the number of lines contained inside my textbox. So I would write
private void my_inherited_txt_code_TextChanged(object sender, EventArgs e)
{
//code to update the label with my_inherited_txt_code.lines.length
}
so my problem was, I first wanted the txt_code_TextChanged event to be called and then do the code written inside my_inherited_txt_code_TextChanged. Which was solved by writing
private void my_inherited_txt_code_TextChanged(object sender, EventArgs e)
{
base.OnTextChanged(e);
MessageBox.Show("foo");
}

Do you mean:
protected override void OnTextChanged(EventArgs e)
{
base.OnTextChanged(e);
// your code here...
}

I cant see why you shouldnt be able to call a method from the text_changed event?
Do you get any errors or what happens exactly?