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How to make the condition to be a Eventhandler Control.click event?

Basically what I am trying to do is, creating a new method that will have an event handler button click event condition within it.enter code here
//when this event is active the only should then should run what inside the {}
if(buttonEvents_Click(object sender, EventArgs e))
{enter code here`
//Happening something
}
what I already tried withing(buttonEvents.click) get the error "the event control.click can only appear on the left side =+ or -+".

You should have your event handler method like you always do:
buttonEvents_Click(object sender, EventArgs e)
{
if(condition){ //you need your condition checker inside the method
//... coder here
}
}
now for any control that you want to add this handler you can sompliy do:
myButton.Click += buttonEvents_Click;
Alternatively you can do this like:
myButton.Click += (s, e) =>
{
//which s is the sender and e is the EventArgs
//code here
};

Remove a dynamically added event handler

I have a code like:
button1.Click += (s, e) =>
{
};
Now how is it possible to remove this handler dynamically? something like:
button1.Click = null;

The point with events is that they are subscribe/unsubscribe, it is not the intention that you should unsubscribe other events then your own. Therefore you need to keep track of your event:
var click = (s, e) =>
{
};
button1.Click += click;
You can then unsubscribe it by:
button1.Click -= click;
EDIT
Seems you can use the approach suggested here.

How to remove the event handler after it had fired?

How to remove the event handler after the event handler had fired so that it can execute only once?
c.Click += (o,e)=>{
Console.WriteLine("Clicked!");
/*I want to remove this event handler now so that it doesn't fire anymore*/
}

You need to store the event handler in a variable, so that you can refer to it later. Because you want to refer to the handler from within the handler you also need to declare it before you initialize it. Finally, you cannot use an uninitialized variable, so you need to initialize it to null first, even though that null value will never be read from.
EventHandler handler = null;
handler = (o,e)=>{
Console.WriteLine("Clicked!");
c.Click -= handler;
}
c.Click += handler;
The other option would be to use a named method, rather than an anonymous method.

This becomes easier if you use a named method instead of an anonymous lambda method.
c.Click += MyHandler;
void MyHandler(object sender, EventArgs e)
{
Console.WriteLine("Clicked!");
((Button)sender).Click -= MyHandler;
}

How to wire up an EventHandler on a Winforms Application?

I have an application and I want to start a countdown timer.
I created an EventHandler under the partial class:
event EventHandler startTimer;
And I wrote a function:
public void startTimerEvent(object sender, EventArgs e)
{
this.Invoke((MethodInvoker)delegate
{
timer.Start();
});
}
How can I register this to the EventHandler and where do I wire it up in my form?

To tie the event to the handler:
startTimer += startTimerEvent;
But I'm not really sure there isn't a better way to go about solving your general problem. If you could describe further what you're after, perhaps we could suggest a better way.

So you need to choose an event that will trigger your handler. Let’s say you have a button, and you want to handle its click event. You could write:
myButton.Click += new EventHandler(StartWhatEver);
Then you would have your StartWhatEver that does what you want.
private void StartWhatEver(object sender, EventArgs e)
{
// Do stuff...
}
Note: If you are working in VS2010, you can type myButton.Click += (with space) then double tap the 'Tab' key and this will create your handler for you automatically including the triggered method.
Hope this helps.

How can I unset the following eventhandler?

I've set an eventhandler to an event like this:
frm.FormClosed += (sender, args) =>
{
if (this.myGrid.Enabled)
{
this.myGrid.Select();
}
};
frm.Show();
I want to hang out the eventhandler after the form was closed.
Can you help me?

I want to hang out the eventhandler after the form was closed.
I assume you want to remove it.
Not necessary, don't waste time on it. When the Form is closed (and Disposed), the eventhandler will be collected too. It is a member of the same Form, that follows from the word this in the code.
If you still want to remove it, you will need a copy:
FormClosedEventhandler closeHandler; // class member
closeHandler = (sender, args) =>
{
if (this.myGrid.Enabled)
{
this.myGrid.Select();
}
};
frm.FormClosed += closeHandler ; // OnLoad
...
frm.FormClosed -= closeHandler ; // OnClose

If you mean how to remove you event handler from the event, then you won't be able to use an anonymous delegate but you can create a method with the same parameters and same code and then:
private void EventHandler(object sender, FormClosedEventArgs e)
{
if (this.myGrid.Enabled)
{
this.myGrid.Select();
}
}
frm.FormClosed += EventHandler; // Attach the event handler
frm.FormClosed -= EventHandler; // Remove the event handler