Question

How can I hide a button when a specific tab is clicked?

for example I have 4 tabs what should I do whenever I click tab 1 a certain button in my
form will disappear?

i’ve tried using if(tabControl.SelectedIndex == 1){ button1.Visible = false; } but it doesn’t work. T_T

Answer 1

You could use the Click event on that particular TabPage

yourTabControl.TabPages[1].Click += (s, e) => button1.Visible = false;

Just remember to show it again when the time is appropriate.

Or better yet, just listen for when the selected tab changes:

yourTabControl.SelectedIndexChanged += (s, e) => {
    if (yourTabControl.SelectedIndex == 1)
        button1.Visible = false;
    } else {
        button1.Visible = true;
    }
};

Or more simply:

yourTabControl.SelectedIndexChanged += (s, e) => 
       button1.Visible = yourTabControl.SelectedIndex != 1;