Question

I am trying to make a tic-tac-toe program, and want to know how I figure out if any of the buttons was clicked and which button it was. I am currently repeating the code inside every button:

private void button1_Click(object sender, EventArgs e)
{
  button1.Visible = false;
  label1.Text = "X";
  Application.DoEvents();

}
private void button2_Click(object sender, EventArgs e)
{
  button2.Visible = false;
  label2.Text = "X";
  Application.DoEvents();
}

private void button3_Click(object sender, EventArgs e)
{
   button3.Visible = false;
   label3.Text = "X"
   Application.DoEvents();
}

Is there a more elegant way to do this?

Answer 1

There’s two ways to accomplish what you’re after (assuming WinForms)..

First, you could wire up all buttons to point to the same event handler.. and check its name:

// In the form designer code:
this.buttonNW.Click += new System.EventHandler(this.button_Click);
this.buttonN.Click += new System.EventHandler(this.button_Click);
this.buttonNE.Click += new System.EventHandler(this.button_Click);


// in the form code:
private void button_Click(object sender, EventArgs e) {
    Button thisButton = (Button)sender;

    switch (thisButton.Name) {
        case "buttonNW":
            MessageBox.Show("North West button clicked");
            break;
        case "buttonN":
            MessageBox.Show("Northern button clicked");
            break;
        case "buttonNE":
            MessageBox.Show("North East button clicked");
            break;
    }
}

Secondly, you could just put the logic into it’s own function and call that function for each individual event handler:

private void buttonNW_Click(object sender, EventArgs e) {
    handleButtonClick("buttonNW");
}

private void buttonN_Click(object sender, EventArgs e) {
    handleButtonClick("buttonN");
}

private void buttonNE_Click(object sender, EventArgs e) {
    handleButtonClick("buttonNE");
}

private void handleButtonClick(string buttonName) {
    switch (buttonName) {
        case "buttonNW":
            MessageBox.Show("North West button clicked");
            break;
        case "buttonN":
            MessageBox.Show("Northern button clicked");
            break;
        case "buttonNE":
            MessageBox.Show("North East button clicked");
            break;
    }
}

I would personally go with option 2 so that everything is clear.

It’s a trivial exercise though, considering you’ll only ever have a maximum of 9 buttons in a tic-tac-toe game.