CPE263 Week 5

Week 5

In C#, loops allow you to repeat a block of code multiple times. One of the common types of loops is the for loop.

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For

A for loop in C# is used when you know in advance how many times you want to execute a block of code.

Components:

1. Initialization: It sets a loop counter to its initial value (e.g., int i = 0).
2. Condition: As long as the condition is true, the loop continues (e.g., i < 10).
3. Iteration: This updates the loop counter after every iteration (e.g., i++).

Project 1

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();
        }

        private void btnUp_Click(object sender, EventArgs e)
        {
            int cnt = 14;
            string strOut = "วนรอบทั้งหมด " + cnt.ToString() + " รอบ" + "\r\n";
            for (int i = 1; i <= cnt; i++)
            {
                strOut += "วนรอบที่ " + i.ToString() + "\r\n";
            }
            txtOut.Text = strOut;
        }

        private void btbDown_Click(object sender, EventArgs e)
        {
            int cnt = 14;
            string strOut = "วนรอบทั้งหมด " + cnt.ToString() + " รอบ" + "\r\n";
            for (int i = cnt; i >= 1; i--)
            {
                strOut += "วนรอบที่ " + i.ToString() + "\r\n";
            }
            txtOut.Text = strOut;
        }

        private void btnStep_Click(object sender, EventArgs e)
        {
            int cnt = 27;
            string strOut = "วนรอบทั้งหมด " + cnt.ToString() + " รอบ" + "\r\n";
            for (int i = 0; i <= cnt; i += 3)
            {
                strOut += "วนรอบที่ " + i.ToString() + "\r\n";
            }
            txtOut.Text = strOut;
        }
    }
}

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

        private void btnRun_Click(object sender, EventArgs e)
        {
            int cnt = 27;
            int step = Convert.ToInt32(txtStep.Text);
            string strOut;

            if (radUp.Checked == true)
            {
                strOut = "วนรอบทั้งหมด " + cnt.ToString() + " รอบ" + "\r\n";
                for (int i = 0; i < cnt; i += step)
                {
                    strOut += "วนรอบที่ " + i.ToString() + "\r\n";
                }
                txtOut.Text = strOut;
            }

            if (radDown.Checked == true)
            {
                strOut = "วนรอบทั้งหมด " + cnt.ToString() + " รอบ" + "\r\n";
                for (int i = cnt; i >= 1; i -= step)
                {
                    strOut += "วนรอบที่ " + i.ToString() + "\r\n";
                }
                txtOut.Text = strOut;
            }
        }
    }
}

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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 WindowsFormsApp4
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btnRun_Click(object sender, EventArgs e)
        {
            int num;
            num = Convert.ToInt16(txtNum.Text);
            string strOut = "";

            for (int i = 1; i <= 12; i++)
            {
                int res = i * num;
                strOut += num.ToString() + "\tX\t" + i.ToString() + "\t=\t" + res.ToString() + "\r\n";
            }
            txtOut.Text = strOut;
        }
    }
}

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Project 4

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 WindowsFormsApp6
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            int i, sum = 0, num = 1;

            for (i = 1; i <= 10; i++)
            {

                sum = sum + num;
                num += 3;
            }
            MessageBox.Show(sum.ToString());
        }

        private void button2_Click(object sender, EventArgs e)
        {
            int i, sum = 0, num = 2;

            for (i = 1; i <= 8; i++)
            {

                sum = sum + num;
                num *= 3;
            }
            MessageBox.Show(sum.ToString());
        }

        private void button3_Click(object sender, EventArgs e)
        {
            int i, sum = 0, num = 0;

            for (i = 1; i <= 10; i++)
            {

                sum = sum + num;
                num += i * 2;
            }
            MessageBox.Show(sum.ToString());
        }

        private void button4_Click(object sender, EventArgs e)
        {
            int i, sum = 0, num = -1;
            int sum2 = 0, num2 = 2;
            int sum3 = 0;

            for (i = 1; i <= 5; i++)
            {

                sum = sum + num;
                num -= 2 ;
            }

            for (i = 1; i <= 5; i ++)
            {

                sum2 = sum2 + num2;
                num2 += 2;
            }

            sum3 = sum2 + sum;

            MessageBox.Show(sum3.ToString());
        }
    }
}