Question

Q1. Create a Windows Form or MFC Dialog-based application that reads and displays an image, and then uses a slider to resize it from 0 to 100% size (zoom out but at different levels)

Answer 1

Following is the C# code for a windows form that loads a image and resizes it according to a slider. Screenshots of successful execution are included at the end for better understanding.

C# CODE:

using System;
using System.Drawing;
using System.Windows.Forms;
 
namespace ImageForm1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
 
        private void Form1_Load(object sender, EventArgs e)
        {
 
        }
 
        private void pictureBox1_Click(object sender, EventArgs e)
        {
 
        }
 
        /*Resizes Image*/
        private void trackBar1_Scroll(object sender, EventArgs e)
        {
            pictureBox1.Size = new Size(trackBar1.Value, trackBar1.Value);
        }
 
        /*Loads Image*/
        private void button1_Click(object sender, EventArgs e)
        {
            OpenFileDialog op = new OpenFileDialog();
 
            if (op.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                pictureBox1.ImageLocation = op.FileName;
            }
        }
    }
}

SCREENSHOT:

1. PictureBox : Properties

2. TrackBar : Properties

Note: Since my Screen Resolution is 720 pixels I Have set the Maximum value to 720.

3.Different states with different Sizes

Image at 100%:

Image at 0%:

Feel free to ask doubts related to this answer in the comments section below, and do leave a thumbs up if this helps.