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how to retrieve text of buttons clicked in windows form with one single method

I have a windows form application with multiple buttons. I need to retrieve the text property of any button clicked in order to create a query to the database. the only way I know is to create a button click event and cast the sender as button then do a switch case for each button Id which seems very hectic since I probably will have more than 100 buttons in the entire application. So my question is there a generic key press method I can create which can retrieve the text property of any button pressed/clicked on the form? Please excuse me if the question is not very clear. Any help will be appreciate

Use a single click event handler for all similar kind of buttons. This way there will be click event subscribed for every button but only one method which will be executed for all buttons. You can determine which button was pressed as follows.
Using sender object as follows;
private void button_Click(object sender, EventArgs e)
{
var buttonText = ((Button)sender).Text;
//Query using buttonText
}
Update:
Above answer will still require you to subscribe click event for each button. If you don't want that then have a look at following approach;
You could use (ClickTransparentButton or) disable (Enabled=false) all these buttons and add click event on parent Form. Once you get click event you can get button which was clicked as follows;
private void Form1_Click(object sender, EventArgs e)
{
var p = PointToClient(Cursor.Position);
var control = GetChildAtPoint(p);
if(control is Button)
{
var buttonText = ((Button)control).Text;
//Query using buttonText
}
}
But this has few disadvantages such as, you will not be able to operate these buttons using keyboard.
and more...

Create some function as buttons click handler:
private void buttonClickHandler(object sender, EventArgs e)
{
string buttonName = (sender as Button).Text;
}
2A. Connect Click event of every button to this handler.
2B. To automate connection of button click handler use something like that:
private void connectButtonsHandlers()
{
foreach(var c in this.Controls)
{
if(c is Button)
{
(c as Button).Click += buttonClickHandler;
}
}
}
Add this code to form constructor to perform connection at program start.

Share an event handler across multiple controls

In my Windows forms application written in C# I have a bunch of buttons. When the user's mouse hovers over a button, I want the button's border to change.
Currently I have multiple instances of the following (a copy for each button):
private void btnStopServer_MouseEnter(object sender, EventArgs e)
{
oldColor = btnStopServer.FlatAppearance.BorderColor;
btnStopServer.FlatAppearance.BorderColor = mouseOverColor;
}
private void btnStopServer_MouseLeave(object sender, EventArgs e)
{
btnStopServer.FlatAppearance.BorderColor = oldColor;
}
Since I have a lot of buttons, the code to change the color of the button's border takes up a lot of space.
Is there any simpler way that I could do this?

You should wire-up a single MouseEnter and MouseLeave to each control that needs this functionality (rather than writing a new version of each method for each control). Assuming you're using Visual Studio, this can be done by changing the target method name for the event, in each Button's property pane. If you write the following code first, then this method will appear in the property's MouseEnter and MouseLeave events' drop-down lists.
The code would then need to check which button from which the event was fired, as follows:
private void btnWithHoverBorder_MouseEnter(object sender, EventArgs e)
{
Button eventButton = (Button) sender;
oldColor = eventButton.FlatAppearance.BorderColor;
eventButton.FlatAppearance.BorderColor = mouseOverColor;
}
private void btnWithHoverBorder_MouseLeave(object sender, EventArgs e)
{
Button eventButton = (Button) sender;
eventButton.FlatAppearance.BorderColor = oldColor;
}
I presume oldColor is a global? This might get out of sync if something "odd" happens where your MouseEnter event is fired for another button, before the corresponding MouseLeave is caught. To make this more robust, I'd consider storing the old color on the Button's .tag property, so that it's self-contained.
Eg:
private void btnWithHoverBorder_MouseEnter(object sender, EventArgs e)
{
Button eventButton = (Button) sender;
eventButton.tag = eventButton.FlatAppearance.BorderColor;
eventButton.FlatAppearance.BorderColor = mouseOverColor;
}
private void btnWithHoverBorder_MouseLeave(object sender, EventArgs e)
{
Button eventButton = (Button) sender;
eventButton.FlatAppearance.BorderColor = (Color)eventButton.tag;
}
(The tag is basically a hook on which to tag "anything" relevant to a specific instance of a control, that there is not already a property for. It's of type Object which means you can tag anything there, but when you read from it, you need to cast it back to whatever type you put there in the first place. But because it's an Object you can put anything there, including eg a custom class that contains multiple properties, or an array, etc if you need to tag a control with more than one thing).

Windows Forms - get Text value from object of type button

I have a Windows form named Form1 and panel within this form named panel1. I use the panel only to place buttons there so that I can group them and work with them separately from the other buttons in my Form1. For the purpose of my program I need to handle every button click made from the buttons inside panel1. For this purpose I use the same code snippet:
public Form1()
{
InitializeComponent();
// Set a click event handler for the button in the panel
foreach (var button in panel1.Controls.OfType<Button>())
{
button.Click += HandleClick;
}
}
What I need to do is to have a way to identify which button exactly has been clicked. For this purpose I played a little bit with my handler method:
private void HandleClick(object o, EventArgs e)
{
MessageBox.Show("HI" + o.ToString());
}
which gave me some hope because I get this:
It's the second part - Text: button4 which is actually enough information to continue with my work. But I can't find a way to get this piece of information without some complicated string manipulations. So is there a way to get this or other unique information about the button been clicked given the way I have written my code?

private void HandleClick(object sender, EventArgs e)
{
var btn = sender as Button;
if (btn != null)
{
MessageBox.Show(btn.Text);
}
}

One option is to cast the object to a Button, but rather than doing the casting you can change how the event handler is assigned so that you don't need to cast in the first place:
foreach (var button in panel1.Controls.OfType<Button>())
{
button.Click += (_,args)=> HandleClick(button, args);
}
Then just change the signature of HandleClick to:
private void HandleClick(Button button, EventArgs e);

You need to cast sender to the Button class so you can access its properties:
Button b = (Button)sender;
MessageBox.Show(b.Text);

Recognizing sender button control in click event

I made a custom button that has a field named Data.
I add this button programatically during runtime to my winform and on adding I also define a click event for them. Well, Actually I only have one method and I subscribe the newly added buttons to this method.
But in the click event I want to access this Data field and show it as a message box, but it seems that my casting is not right:
CustomButton_Click(object sender, EventArgs e)
{
Button button;
if (sender is Button)
{
button = sender as Button;
}
//How to access "Data" field in the sender button?
//button.Data is not compiling!
}
UPDATE:
I am sorry, I ment with "is not compiling" that .Data does not show up in intelisense...

You need to cast to the type of your custom class that has the Data field.
Something like:
YourCustomButton button = sender as YourCustomButton;

Assuming your custom button type is CustomButton, you should do this instead:
CustomButton_Click(object sender, EventArgs e){
CustomButton button = sender as CustomButton;
if (button != null){
// Use your button here
}
}

If you dont want to set a variable the simple way to do is:
((CustomButton)sender).Click
or whatever you want.

I found a funny check assignment in a win forms project on Github:
private void btn_Click(object sender, EventArgs e){
// here it checks if sender is button and make the assignment, all in one shot.
// Bad readability, thus not recommended
if (!(sender is Button senderButton))
return;
var _text = senderButton.Text;
...

Radio button checked changed event fires twice

Please read my question its not a duplicate one.
I've three radio buttons on windows form and all these buttons have common 'CheckedChanged' event associated. When I click any of these radio buttons, it triggers the 'CheckedChanged' event twice.
Here is my code:
private void radioButtons_CheckedChanged(object sender, EventArgs e)
{
//My Code
}
I inserted the breakpoint and the whole code within this event iterates twice.
Please tell me why it is behaving like this?

As the other answerers rightly say, the event is fired twice because whenever one RadioButton within a group is checked another will be unchecked - therefore the checked changed event will fire twice.
To only do any work within this event for the RadioButton which has just been selected you can look at the sender object, doing something like this:
void radioButtons_CheckedChanged(object sender, EventArgs e)
{
RadioButton rb = sender as RadioButton;
if (rb != null)
{
if (rb.Checked)
{
// Only one radio button will be checked
Console.WriteLine("Changed: " + rb.Name);
}
}
}

To avoid it, just check if radioButton is checked
for example:
private void radioButton1_CheckedChanged(object sender, EventArgs e)
{
if (radioButton1.Checked)
//your code
}

CheckedChanged is raised whenever the Checked property changes. If you select a RadioButton then the previously selected RadioButton is unchecked (fired CheckedChanged), and then the new RadioButton is checked (fired CheckedChanged).

It's triggering once for the radio button transition from checked to unchecked, and again for the radio button transitioning from unchecked to checked (i.e. any change in checked state triggers the event)

You could set the AutoCheck property true for each RadioButton then catch the Click event instead of the CheckChanged event. This would ensure that only one event is fired, and the logic in the handler can cast the sender to type RadioButton if needed to process the click. Often the cast can be avoided if the handler logic is simple. Here is an example which handles three controls, rbTextNumeric, rbTextFixed and rbTextFromFile:
private void rbText_Click(object sender, EventArgs e)
{
flowLayoutPanelTextNumeric.Enabled = rbTextNumeric.Checked;
txtBoxTextFixed.Enabled = rbTextFixed.Checked;
flowLayoutPanelTextFromFile.Enabled = rbTextFromFile.Checked;
}

{
public partial class Form3 : Form
{
public Form3()
{
InitializeComponent();
}
int click = 0;
private void radioButton1_Click(object sender, EventArgs e)
{
click++;
if (click %2==1)
{
radioButton1.Checked = true;
}
if (click %2==0)
{
radioButton1.Checked = false;
}
if (radioButton1.Checked==true)
{
label1.Text = "Cheked";
}
if (radioButton1.Checked==false)
{
label1.Text = "Uncheked";
}
}
}
}

The other answers are correct but miss the reason for the underlying problem.
When a radio button is checked the first event sent is the change from the unchecked item
however if you check its state by its control name you will still see its old checked status because the form has not been updated yet. To see its true status you need to cast the sender object.
This allows you to perform any actions relating to the condition which is being deselected should you need to do so.
In the not uncommon scenario below multiple radio buttons are sent to the same handler event.
Simply checking the state of the sender for checked will not work here as we need to perform different actions depending on which radio button has been pressed.
So first we ignore any sender that has just been unchecked.
then we identify the checked sender by control name to process the correct action.
private void ModeChangedExample(object sender, EventArgs e)
{
// multiple radio buttons come here
// We only want to process the checked item.
// if you need to something based on the item which was just unchecked don't use this technique.
// The state of the sender has not been updated yet in the form.
// so checking against rdo_A check state will still show it as checked even if it has just been unchecked
// only the sender variable is up to date at this point.
// To prevent processing the item which has just been uncheked
RadioButton RD = sender as RadioButton;
if (RD.Checked == false) return;
if (rdo_A.Name == RD.Name)
{
//Do stuff
}
if (rdo_B..Name == RD.Name)
{
// Do other stuff
}
if (rdo_C.Name == RD.Name)
{
// Do something else
}
}

This problem of double checking happens when there is a series of RadioButton Clicks in succession.I had this same problem.The last click will give two results.To overcome this i made a dummy click in the end.The double click stopped.Try this method.
Venkatraman