程序代码：

class Test
{
    static void button_Click(object button, EventArgs args)
    {
        MessageBox.Show("Submitted!");
    }

    static void Main()
    {
        Button button = new Button { Text = "Submit", Top = 40 };
        button.Click += button_Click;

        TextBox textBox = new TextBox();
        textBox.KeyPress += (s, a) =>
            {
                if (a.KeyChar == 13)
                {
                    button_Click(null, null);
                }
            };

        Form form = new Form();
        form.Controls.Add(textBox);
        form.Controls.Add(button);

        Application.Run(form);
    }
}