WPF - Image


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A control that displays an image, you can use either the Image object or the ImageBrush object. An Image object display an image, while an ImageBrush object paints another object with an image. The image source is specified by referring to an image file using several supported formats. It can display the following formats −

  • Bitmap (BMP)
  • Tagged Image File Format (TIFF)
  • Icons (ICO)
  • Joint Photographic Experts Group (JPEG)
  • Graphics Interchange Format (GIF)
  • Portable Network Graphics (PNG)
  • JPEG XR

The hierarchical inheritance of Image class is as follows

Hierarchical of Image

Commonly Used Properties of Image class

Sr.No. property & Description
1

CanDrag

Gets or sets a value that indicates whether the element can be dragged as data in a drag-and-drop operation. (Inherited from UIElement)

2

Height

Gets or sets the suggested height of a FrameworkElement. (Inherited from FrameworkElement)

3

HorizontalAlignment

Gets or sets the horizontal alignment characteristics that are applied to a FrameworkElement when it is composed in a layout parent, such as a panel or items control. (Inherited from FrameworkElement)

4

Margin

Gets or sets the outer margin of a FrameworkElement. (Inherited from FrameworkElement)

5

Name

Gets or sets the identifying name of the object. When a XAML processor creates the object tree from XAML markup, run-time code can refer to the XAML-declared object by this name. (Inherited from FrameworkElement)

6

Opacity

Gets or sets the degree of the object's opacity. (Inherited from UIElement)

7

PlayToSource

Gets the information that is transmitted if the Image is used for a Play To scenario.

8

Resources

Gets the locally defined resource dictionary. In XAML, you can establish resource items as child object elements of a frameworkElement.Resources property element, through XAML implicit collection syntax. (Inherited from FrameworkElement)

9

SourceProperty

Identifies the Source dependency property.

10

Stretch

Gets or sets a value that describes how an Image should be stretched to fill the destination rectangle.

11

StretchProperty

Identifies the Stretch dependency property.

12

Style

Gets or sets an instance Style that is applied for this object during layout and rendering. (Inherited from FrameworkElement)

13

VerticalAlignment

Gets or sets the vertical alignment characteristics that are applied to a FrameworkElement when it is composed in a parent object such as a panel or items control. (Inherited from FrameworkElement)

14

Width

Gets or sets the width of a FrameworkElement. (Inherited from FrameworkElement)

15

wSource

Gets or sets the source for the image.

Commonly Used Events of Image Class

Sr.No. Event & Description
1

DataContextChanged

Occurs when the value of the FrameworkElement.DataContext property changes. (Inherited from FrameworkElement)

2

DragEnter

Occurs when the input system reports an underlying drag event with this element as the target. (Inherited from UIElement)

3

DragLeave

Occurs when the input system reports an underlying drag event with this element as the origin. (Inherited from UIElement)

4

DragOver

Occurs when the input system reports an underlying drag event with this element as the potential drop target. (Inherited from UIElement)

5

DragStarting

Occurs when a drag operation is initiated. (Inherited from UIElement)

6

Drop

Occurs when the input system reports an underlying drop event with this element as the drop target. (Inherited from UIElement)

7

DropCompleted

Occurs when a drag-and-drop operation is ended. (Inherited from UIElement)

8

GotFocus

Occurs when a UIElement receives focus. (Inherited from UIElement)

9

ImageFailed

Occurs when there is an error associated with image retrieval or format.

10

ImageOpened

Occurs when the image source is downloaded and decoded with no failure. You can use this event to determine the natural size of the image source.

11

KeyDown

Occurs when a keyboard key is pressed while the UIElement has focus. (Inherited from UIElement)

12

KeyUp

Occurs when a keyboard key is released while the UIElement has focus. (Inherited from UIElement)

13

SizeChanged

Occurs when either the ActualHeight or the ActualWidth property changes value on a FrameworkElement. (Inherited from FrameworkElement)

Example

  • Let’s create a new WPF project with the name WPFImageControl.

  • First divide the screen into two rows by using Grid.RowDefinition.

  • Drag three Image controls from the Toolbox.

  • The following example shows three images. The first one is a simple image; in the second image, opacity property is set; and in the third image, one Eclipse is painted with an ImageBrush.

  • The XAML code is as follows −

<Window x:Class = "WPFImageControl.MainWindow" 
   xmlns = "http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
   xmlns:x = "http://schemas.microsoft.com/winfx/2006/xaml" 
   Title = "MainWindow" Height = "500" Width = "604">
	
   <Grid> 
      <Grid.RowDefinitions> 
         <RowDefinition Height = "1*"/> 
         <RowDefinition Height = "1*"/> 
      </Grid.RowDefinitions>
		
      <StackPanel Orientation = "Horizontal"> 
         <Image Width = "200" Source = "Images\red_rock_01.jpg"  
            VerticalAlignment = "Top" Margin = "30"/> 
         <Image Width = "200" Source = "Images\red_rock_01.jpg" VerticalAlignment = "Top"
            Margin = "30" Opacity = "0.5"/>             
      </StackPanel> 
		
      <StackPanel Grid.Row = "1"> 
         <Ellipse Height = "100" Width = "200" HorizontalAlignment = "Center" Margin = "30"> 
            <Ellipse.Fill> 
               <ImageBrush ImageSource = "Images\tahoe_01.jpg" /> 
            </Ellipse.Fill> 
         </Ellipse> 
      </StackPanel> 
		
   </Grid> 
	
</Window>

When you compile and execute the above code, it will produce the following window −

Output of Image

We recommend that you execute the above example code and try the other properties and events of the Image class.


wpf_controls.htm

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