Develop Reference

How to print the name of the button which is clicked in C#?

I am adding dynamic buttons to the form with button click. And the whole buttons has same names. Also i add toolstripmenu to all buttons. I want to do is when i press to the DeleteCity from ToolStripMenu, my button must be remove from my form. I tried to remove it like this:
this.Controls.Remove(-button_name-);
But i dont know the name of the button.How to i reach the clicked button name? Thanks for your help.

In your eventhandler of the button_clicked event you get the sender of the click event (e.g. the button). You can get all the buttons information including the name from this.
It could look something like this:
private void Button_Click(object sender, RoutedEventArgs e)
{
Button button = sender as Button;
var test = button.Name;
}

clear mutiple textboxes by reusing an event handler

I have 3 textboxes and I need to clear the text once the text box is clicked.
The only thing is that I have to do that by reusing the same event handler. I created the event handler, gave it a general name to fit all, but now I don't know what statement to write inside it.
if I write : txtBox1.Clear(); it will only clear that one textbox, but if I write: txtBox1.Clear(); txtBox2.Clear(); txtBox3.Clear();
It will clear all of them when only one is clicked.
In other words, I need it to clear only the text of the textbox that has been clicked, but they all have to be under the same event handler.
Anything will help! thanks!

You can assign the same event handler to all the textBoxes and use sender parameter to get the real sender.
private void textBox_Click(object sender, EventArgs e)
{
TextBox textBox = sender as TextBox;
if (textBox != null)
{
textBox.Clear();
}
}

How to generate events automatically for buttons without creating manually from properties if there are 'n' number of buttons?

IDE: Visual Studio 2010
Language: c# .net
I am generating events for buttons manually from properties. But, its becoming very lengthy process if there are suppose 20 buttons doing the same task like 'Mouse Hover' and 'Mouse Leave' . So, is there a way to copy events for all the other buttons ?

You can subscribe all your buttons to same event handler:
foreach(var button in Controls.OfType<Button>())
{
button.MouseHover += Button_MouseHover; // add handler
button.MouseLeave += Button_MouseLeave;
}
In that handler you can determine which exact button raised even by casting event source to button type:
private void Button_MouseHover(object sender, EventArgs e)
{
var button = (Button)sender; // sender is one of buttons
// use button.Name
}
Code above subscribes to events of all buttons. But if you want to filter them (e.g. by name) you can add filtering:
Controls.OfType<Button>().Where(b => b.Name.StartsWith("foo"))

Buttons can all share the same event, there's no need to have a seperate event for each button if they're doing similar tasks. (The object sender parameter will give you the Control which was clicked.
IF you select all the buttons (by keeping the ctrl key pressed) in the designer, you can then easily assign 1 event to all 20 buttons

In life you will not find shortcuts for everything,
In short there is no shortcut, but yes as mentioned in other post if you have same event handler and same action to be taken then this will help you reduce your work.

You don't have to do this manually, you can add event handlers from code as well. Also, if the logic is quite similar for all the buttons then you can use single event handler for all of them. Every event handler has sender property what will be set to the button that caused event.
Simple example would be something like this:
//at first assign event handlers
button1.Click += new EventHandler(Button_Click);
button2.Click += new EventHandler(Button_Click);
//single event handler
private void Button_Click(object sender, System.EventArgs e)
{
// Add event handler code here.
Debug.WriteLine("You clicked: {0}", sender);
}

Problems with KeyPressEventArgs

here's my problem .. i'm doing a calculator in C# and i don't want to click every single button to make a operation, i wanna handle it with my num pad .. like
if i press "1" , show me in the textbox "1".
i changed
private void cmd1_Click(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == '1')
{
txtShow.Text='1';
}
}
and i'm having this error :
No overload for 'cmd1_Click' matches delegate "System.EventHandler"
this.cmd1.Click += new System.EventHandler(this.cmd1_Click);
what the hack is wrong with this?
Cheers.

change
this.cmd1.Click += new System.EventHandler(this.cmd1_Click);
to
this.cmd1.KeyPress += new System.EventHandler(this.cmd1_Click);
You'll probably want to rename cmd1_Click too.
And as mentioned in the answer above, this would be better on the Form itself, rather than each button.

You are trying to attach an event handler that corresponds to a KeyPress event to a Click event.
There is something wrong here (bad copy/paste?):
private void cmd1_Click(object sender, KeyPressEventArgs e)
It's named as an auto-generated event handler for the Click event on cmd1, but its definition is the definition for a KeyPress event handler.
Which event do you want to handle? KeyPress or Click or both?

Click is a mouse event, you need to attach to a keyboard event if you want to receive keyboard event args, you'd have to put all your calculator buttons in a common pannel and handle both the button click "and" the text being sent to the panel, that way you could react to both keypresses anywhere and to click for the same result.
An easy way to handling events for all the buttons without doing it one by one is to have a single button click handler and check the text property of the control to know how to act (cast the sender to a button and check the text, do a switch on that)
Not tested:
switch(((button)sender).Text)
{
case "1":
// react to user having pressed 1 etc etc
}

Check for Button Click Event on Form - C#

I currently have a form with about 13 buttons on it.
I want to be able to perform a function when one of those buttons are clicked. But I am trying to keep from having 13 different button click events.
Is there some way for me to be able to determine when any button click event is fired, and be able to tell which button fired it?
Thanks!

Have one function that handles all of the click events and use the properties of the 'sender' object to identify the specific button.

You can have different button click handlers, and name them according to button actions, also you can have single event handler for all of them, in this case parameter sender can be cast to button and for example by it's name, finding related button.
But I offer if you have similar behavior on group of buttons map them to a single function, but if actions are different using different method is better, but in all one form with 13 button is not good, you can change them to menu, Tab, ...

foreach (Control ctl in this.Controls)
{
if (ctl is Button)
(ctl as Button).Click += MyButtonHandler;
}
protected void MyButtonHandler(object sender, EventArgs e)
{
Button clickedButton = sender as Button;
//...
}

The first parameter to the callback function is the button that was pressed.

private void OnButtonClicked(object sender, EventArgs e){
Button oButton = sender as Button;
if (oButton != null){
// your logic goes here !
}
}
oButton variables is your current button. (important to check if oButton != null when using as operator)

on the click event you get a reference to the Sender - this is the clicked button so inside that you could test for the Content or Tag and act based on the value:
private void Button_Click(object sender, RoutedEventArgs e)
{
MessageBox.Show((sender as Button).Tag.ToString());
}

I think that in this situation using delgates would be proper. Check these links out for further information on implementation.
The C# Station Tutorial: Introduction to Delegates and Events
Delegates and Events in C# / .NET

Every proper eventhandler has an Object sender parameter. Give all 13 buttons the same handler by typing the same name in the Properties window OnClick event, for instance: OnAnyButtonClicked. The created function will be:
private void OnAnyButtonClicked(object sender, ...)
{
// sender is the button that was clicked,
// find out which button is clicked
// call the corresponding function
}
Tip:
To find out which button is pressed you could use Object.ReferenceEquals
A faster way to avoid if ... then ... else if ... then ... else if...
is using the Tag property of each Button.
Give eacht Button.Tag an enum value corresponding to the action that has to be performed and use a switch statement to find out what has to be done.
You could also assing a delegate to the button.Tag, but that is almost the same as making a different onClick event handler for every button.