List<Button> List1 = new();
private void Form1_Load(object sender, EventArgs e)
{
List1.Add(button1);
List1.Add(button2);
List1.Add(button3);
foreach (var item in List1)
{
item.Click += Item_Click;
}
}
private void Item_Click(object? sender, EventArgs e)
{
Text = ((Button)sender!).Text;
}