WinForms AcceptButton not working?

Question

Ok, this is bugging me, and I just can't figure out what is wrong...

I have made two forms. First form just has a simple button on it, which opens the other as a dialog like so:

using (Form2 f = new Form2())
{
    if (f.ShowDialog() != DialogResult.OK)
        MessageBox.Show("Not OK");
    else
        MessageBox.Show("OK");
}

The second, which is that Form2, has two buttons on it. All I have done is to set the forms AcceptButton to one, and CancelButton to the other. In my head this is all that should be needed to make this work. But when I run it, I click on the button which opens up Form2. I can now click on the one set as CancelButton, and I get the "Not OK" message box. But when I click on the one set as AcceptButton, nothing happens? The InitializeComponent code of Form2 looks like this:

private void InitializeComponent()
{
    this.button1 = new System.Windows.Forms.Button();
    this.button2 = new System.Windows.Forms.Button();
    this.SuspendLayout();
    // 
    // button1
    // 
    this.button1.Location = new System.Drawing.Point(211, 13);
    this.button1.Name = "button1";
    this.button1.Size = new System.Drawing.Size(75, 23);
    this.button1.TabIndex = 0;
    this.button1.Text = "button1";
    this.button1.UseVisualStyleBackColor = true;
    // 
    // button2
    // 
    this.button2.DialogResult = System.Windows.Forms.DialogResult.Cancel;
    this.button2.Location = new System.Drawing.Point(130, 13);
    this.button2.Name = "button2";
    this.button2.Size = new System.Drawing.Size(75, 23);
    this.button2.TabIndex = 1;
    this.button2.Text = "button2";
    this.button2.UseVisualStyleBackColor = true;
    // 
    // Form2
    // 
    this.AcceptButton = this.button1;
    this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
    this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
    this.CancelButton = this.button2;
    this.ClientSize = new System.Drawing.Size(298, 59);
    this.Controls.Add(this.button2);
    this.Controls.Add(this.button1);
    this.Name = "Form2";
    this.Text = "Form2";
    this.Load += new System.EventHandler(this.Form2_Load);
    this.ResumeLayout(false);
}

I have done nothing else than add those two buttons, and set the AcceptButton and CancelButton. Why doesn't it work?

Answer 1

Just setting the AcceptButton/CancelButton is not enough. This just tells which button should be invoked on Enter/Esc. You have to set the DialogResult in the Button handler.