CPE263 Week 7

Week 7

In C#, a method is a block of code that performs a specific task and can be called upon when needed. Methods help organize code and avoid redundancy.

Method

Key Components of a C# Method: 1. Access Modifier: Defines visibility (public, private, etc.). 2. Return Type: Data type returned by the method (void if none). 3. Method Name: Identifier for the method (PascalCase). 4. Parameters: Optional inputs for the method.

Project 1

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        void SayHello()
        {
            MessageBox.Show("Hello");
        }

        void ShowMessage(string message)
        {
            MessageBox.Show(message);
        }

        double CalculateTotal(int quantity, double price)
        {

            double total = quantity * price;
            return total;

        }

        string OddEven(int num)
        {

            if (num % 2 == 0)
                return "Even";
            else
                return "Odd" ;

        }

        int Max(int num1, int num2)
        {

            if (num1 > num2)
                return num1;
            else
                return num2;

        }

        private void button1_Click(object sender, EventArgs e)
        {
            //SayHello();
            //ShowMessage("Hello100");

            //double y = CalculateTotal(2, 5);
            //MessageBox.Show(y.ToString());

            //string y = OddEven(2);
            //MessageBox.Show(y);

            int y = Max(2, 5);
            MessageBox.Show(y.ToString());
        }
    }
}

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Project 2

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        string Number(int x)
        {
            if (x > 0)
            {
                return "จำนวนเต็มบวก";
            }
            else if (x < 0)
            {
                return "จำนวนเต็มลบ";
            }
            else
            {
                return "จำนวนเต็มศูนย์";
            }
        }

        double Vat(int x)
        {
            return  x * 0.07;
        }

        private void btn1_Click(object sender, EventArgs e)
        {
            int num = Convert.ToInt32(txtNumber.Text);
            string y = Number(num);
            MessageBox.Show(y);
        }

        private void btn2_Click(object sender, EventArgs e)
        {
            int price = Convert.ToInt32(txtPrice.Text);
            double vat = Vat(price);

            MessageBox.Show("Price : " +  price.ToString() +
                            "\r\nVat 7 % : "+  vat.ToString());
        }
    }
}

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Project 3

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void setDate()
        {
            string day = updDate.Value.ToString();
            string month = updMonth.Value.ToString();
            string year = updYear.Value.ToString();
            string dateStr = month + "/" + day + "/" + year;

            DateTime dt;

            if(DateTime.TryParse(dateStr,out dt))
            {
                monthCalendar1.SetDate(dt);
            }
            else
            {
                MessageBox.Show("รูปแบบวันเดือนปีไม่ถูกต้อง");
            }

        }

        private void Form1_Load(object sender, EventArgs e)
        {
                updYear.Value = DateTime.Today.Year;
                updDate.Value = DateTime.Today.Day;
                updMonth.Value = DateTime.Today.Month;
        }

        private void updDate_ValueChanged(object sender, EventArgs e)
        {
            setDate();
        }

        private void updMonth_ValueChanged(object sender, EventArgs e)
        {
            setDate();
        }

        private void updYear_ValueChanged(object sender, EventArgs e)
        {
            setDate();
        }

        private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (comboBox1.SelectedItem.ToString() == "จันทร์")
            {
                monthCalendar1.FirstDayOfWeek = Day.Monday;
            }else
            {
                monthCalendar1.FirstDayOfWeek = Day.Sunday;
            }
        }
    }
}