在点击事件中识别发件人按钮控件

Question

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...

Answer 1

You need to cast to the type of your custom class that has the Data field.

Something like:

YourCustomButton button = sender as YourCustomButton;

Answer 2

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
  } 
}

Answer 3

If you dont want to set a variable the simple way to do is:

((CustomButton)sender).Click

or whatever you want.

Answer 4

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;
...