[C#] If-else คำนวณเกรด

โค้ด
namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string strOut = "";

            if (textBox1.Text == "")
            {
                MessageBox.Show("You did not fill any scores, Please fill again", "Result of your scores", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            else
            {
                int score = int.Parse(textBox1.Text);

                if (score < 0 || score > 100)
                {
                    strOut = "Incorrect Input, Please fill again.";
                }
                else if (score < 50)
                {
                    strOut = "Your scores are " + score + ", Grade 0 : Fail";
                }
                else if (score < 60)
                {
                    strOut = "Your scores are " + score + ", Grade 1 : Poor";
                }
                else if (score < 70)
                {
                    strOut = "Your scores are " + score + ", Grade 2 : Fair";
                }
                else if (score < 80)
                {
                    strOut = "Your scores are " + score + ", Grade 3 : Good";
                }
                else
                {
                    strOut = "Your scores are " + score + ", Grade 4 : Very Good";
                }

                MessageBox.Show(strOut, "Result of your scores", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
        }

    }
}
Verzaru's Notes

[C#] If-else คำนวณเกรด
