1. MDI Picture Viewer Application

2. New Project - An MDI Picture Viewer

3. Main Form Settings and Controls
New Project - Windows Forms Application
Menu Strip
drop a MenuStrip onto the main form
create tabs for File and Edit
under File include
New
Open
Save
Save As
Close
we will work on Open and Save First
create Click-Events for these two....
Property Setting
Name FormMain
IsMdiContainer True
Text Whatever Name you Want
WindowState Maximized

4. Adding a Child Form
Click on the Project Tab and Select Add Windows Form frmChild
Add a PictureBox control
Property Setting
Name frmChild
Anchor Top,Bottom,Left,Right
Dock Fill

5. The loadImage( ) Method
public void loadImage(string fname) {
int minWidth = 100;
int minHeight = 50;
int maxWidth = 1024;
int maxHeight = 800;
Bitmap img = new Bitmap(fname);
picBox.Image = img;
if (img.Width + 15 > minWidth)
this.Width = img.Width + 15;
else
this.Width = minWidth;
if (img.Height > minHeight)
this.Height = img.Height + 40;
this.Height = minHeight;
if (img.Width > maxWidth)
this.Width = maxWidth;
if (img.Height > maxHeight)
this.Height = maxHeight; }
This method is placed in the frmChild Code and resets the
Child form size based on the picture.
makes sure the Child form is not too small in case a very small
image is loaded.
The maximum size of the Child form is set to1024 x 800, which
means that images larger than this will be clipped. We can
manually resize the Child form but we may load pictures larger
than our computer monitor can display.

6. Dealing with Very Large Images
We can add scrollbars to the image.
remove the pictureBox and add a Panel to
the Child Form...set the following properties:
AutoSize = true
Dock = Fill
add a pictureBox (called picBox) to the Panel
with the following property
SizeMode = AutoSize
leave all other properties in their default settings

8. Opening an Image in a Child Form
private void openImage() {
string fileName = "";
OpenFileDialog dlg = new OpenFileDialog();
dlg.Filter = "JPEG files (*.jpg)|*.jpg|GIF files (*.gif)|*.gif|Bitmap files (*.bmp)|*.bmp|PNG files (*.png)|*.png";
if (dlg.ShowDialog() == DialogResult.OK)
fileName = dlg.FileName;
Bitmap img = new Bitmap(fileName);
makeNewMdiChild();
frmChild activeChild = this.ActiveMdiChild as frmChild;
activeChild.Text = fileName;
activeChild.loadImage(fileName); }
private void openToolStripMenuItem_Click(object sender, EventArgs e)
openImage();
private void makeNewMdiChild()
PictureViewer.frmChild child = new PictureViewer.frmChild(this);
child.Show();
this.ActiveMdiChild.Text = "New-File-" + Convert.ToString(newindex);
newindex += 1;
permits us to access .jpg, .gif, .bmp, and .png image files
converts incoming image into a bitmap
opens a Child form
renames the Child form to the image path/filename
note that in this case we have created a separate method named openImage( ) that is called inside
the Click-Event for Open under the File tab...the code in openImage( ) could have been placed
directly into the openToolStripMenuItem_Click( ) method.

9. Example Execution

10. Adding Scrollbars to the Picture Box
Sometimes an image will be larger than the Child form window or even the computer monitor. In these cases we will want to be able to scroll the image to see it all. In order to make the image scrollable you can place the pictureBox inside a panel with the following property settings…
panel1
AutoScroll True
AutoSize True
Dock Fill
picBox
Dock None
SizeMode AutoSize