Image Zoom

   
  
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

public class Form1 : System.Windows.Forms.Form {
    private System.Windows.Forms.Label label1= new System.Windows.Forms.Label();
    private System.Windows.Forms.GroupBox groupBox1= new System.Windows.Forms.GroupBox();
    private System.Windows.Forms.RadioButton radioButton1= new System.Windows.Forms.RadioButton();
    private System.Windows.Forms.RadioButton radioButton2= new System.Windows.Forms.RadioButton();
    private System.Windows.Forms.RadioButton radioButton3= new System.Windows.Forms.RadioButton();
    private System.Windows.Forms.RadioButton radioButton4= new System.Windows.Forms.RadioButton();
    private System.Windows.Forms.Label label2= new System.Windows.Forms.Label();
    private System.Windows.Forms.CheckBox checkBox1= new System.Windows.Forms.CheckBox();

    Image im = null;
    Image im2 = null;
    public Form1() {
        this.groupBox1.SuspendLayout();
        this.SuspendLayout();
        this.label1.Location = new System.Drawing.Point(8, 16);
        this.label1.Size = new System.Drawing.Size(200, 240);
        this.groupBox1.Controls.AddRange(new System.Windows.Forms.Control[] {
                                          this.checkBox1,
                                          this.radioButton1,
                                          this.radioButton2,
                                          this.radioButton3,
                                          this.radioButton4});
        this.groupBox1.Location = new System.Drawing.Point(232, 48);
        this.groupBox1.Size = new System.Drawing.Size(72, 128);
        this.checkBox1.Location = new System.Drawing.Point(8, 32);
        this.checkBox1.Size = new System.Drawing.Size(56, 24);
        this.checkBox1.CheckedChanged += new System.EventHandler(this.checkBox1_CheckedChanged);
        this.radioButton1.Location = new System.Drawing.Point(8, 64);
        this.radioButton1.Size = new System.Drawing.Size(16, 24);
        this.radioButton2.Location = new System.Drawing.Point(40, 64);
        this.radioButton2.Size = new System.Drawing.Size(16, 24);
        this.radioButton3.Location = new System.Drawing.Point(8, 96);
        this.radioButton3.Size = new System.Drawing.Size(16, 24);
        this.radioButton4.Location = new System.Drawing.Point(40, 96);
        this.radioButton4.Size = new System.Drawing.Size(16, 24);

        this.label2.Location = new System.Drawing.Point(328, 16);
        this.label2.Size = new System.Drawing.Size(200, 240);

        this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
        this.ClientSize = new System.Drawing.Size(536, 266);
        this.Controls.AddRange(new System.Windows.Forms.Control[] {
                                      this.groupBox1,
                                      this.label1,
                                      this.label2});
        this.groupBox1.ResumeLayout(false);
        this.ResumeLayout(false);
        this.Text = "Zooming";
        this.label1.Text = "";
        this.groupBox1.Text = "Zoom";
        this.checkBox1.Text = "Paint";
        this.radioButton1.Checked = false;
        this.radioButton1.CheckedChanged += new System.EventHandler(this.radioButtons_CheckedChanged);
        this.radioButton2.CheckedChanged += new System.EventHandler(this.radioButtons_CheckedChanged);
        this.radioButton3.CheckedChanged += new System.EventHandler(this.radioButtons_CheckedChanged);
        this.radioButton4.CheckedChanged += new System.EventHandler(this.radioButtons_CheckedChanged);
    }

    [STAThread]
    static void Main() {
        Application.Run(new Form1());
    }
    protected override void OnPaint(PaintEventArgs e) { ImageZoom(); }
    private void checkBox1_CheckedChanged(object sender, System.EventArgs e) { ImageZoom(); }
    private void radioButtons_CheckedChanged(object sender, System.EventArgs e) { ImageZoom(); }
    protected void ImageZoom() {
        Graphics g1 = Graphics.FromHwnd(this.label1.Handle);
        Graphics g2 = Graphics.FromHwnd(this.label2.Handle);
        Rectangle rec;
        Rectangle recPart;

        if (this.checkBox1.Checked) {
            if (im == null) ReadImage();

            rec = new Rectangle(0, 0, label1.Width, label1.Height);
            g1.DrawImage(im, rec);

            recPart = new Rectangle(im.Width / 4, im.Height / 4, im.Width / 2, im.Height / 2);
            if (this.radioButton1.Checked)
                recPart = new Rectangle(0, 0, im.Width / 2, im.Height / 2);
            if (this.radioButton2.Checked)
                recPart = new Rectangle(im.Width / 2, 0, im.Width / 2, im.Height / 2);
            if (this.radioButton3.Checked)
                recPart = new Rectangle(0, im.Height / 2, im.Width / 2, im.Height / 2);
            if (this.radioButton4.Checked)
                recPart = new Rectangle(im.Width / 2, im.Height / 2, im.Width / 2, im.Height / 2);
            g2.DrawImage(im, rec, recPart, GraphicsUnit.Pixel);
        } else {
            Clear(g1);
            Clear(g2);
        }

        g1.Dispose(); g2.Dispose();
    }
    protected void ReadImage() {
        string path = "3.BMP";
        im = Image.FromFile(path);
        this.radioButton1.Enabled = true;
        this.radioButton2.Enabled = true;
        this.radioButton3.Enabled = true;
        this.radioButton4.Enabled = true;
    }
    protected void Clear(Graphics g) {
        g.Clear(this.BackColor);
        g.Dispose();
        im = null;
        im2 = null;
        this.radioButton1.Checked = false;
        this.radioButton2.Checked = false;
        this.radioButton3.Checked = false;
        this.radioButton4.Checked = false;

        this.radioButton1.Enabled = false;
        this.radioButton2.Enabled = false;
        this.radioButton3.Enabled = false;
        this.radioButton4.Enabled = false;
    }
}