Graphics.DrawImage Method (Image, Point(), Rectangle, GraphicsUnit, ImageAttributes)

 

Draws the specified portion of the specified Image at the specified location.

Namespace:   System.Drawing
Assembly:  System.Drawing (in System.Drawing.dll)

Public Sub DrawImage (
	image As Image,
	destPoints As Point(),
	srcRect As Rectangle,
	srcUnit As GraphicsUnit,
	imageAttr As ImageAttributes
)

Parameters

image
Type: System.Drawing.Image

Image to draw.

destPoints
Type: System.Drawing.Point()

Array of three Point structures that define a parallelogram.

srcRect
Type: System.Drawing.Rectangle

Rectangle structure that specifies the portion of the image object to draw.

srcUnit
Type: System.Drawing.GraphicsUnit

Member of the GraphicsUnit enumeration that specifies the units of measure used by the srcRect parameter.

imageAttr
Type: System.Drawing.Imaging.ImageAttributes

ImageAttributes that specifies recoloring and gamma information for the image object.

Exception Condition
ArgumentNullException

image is null.

The destPoints parameter specifies three points of a parallelogram. The three Point structures represent the upper-left, upper-right, and lower-left corners of the parallelogram. The fourth point is extrapolated from the first three to form a parallelogram.

The srcRect parameter specifies a rectangular portion of theimage object to draw. This portion is scaled and sheared to fit inside the parallelogram specified by the destPoints parameter.

The following code example is designed for use with Windows Forms, and it requires PaintEventArgse, which is a parameter of the Paint event handler. The code performs the following actions:

  • Creates an image from a JPEG file SampImag.jpg in the folder of the example.

  • Creates points that define a parallelogram in which to draw the image.

  • Creates a rectangle to select the portion of the image to draw.

  • Sets the graphics drawing unit to pixel.

  • Draws the original image to the screen.

  • Creates an additional parallelogram in which to draw an adjusted image.

  • Creates and sets the attributes of the adjusted image to have a larger-than-usual gamma value.

  • Draws the adjusted image to the screen.

For the original, unadjusted parallelogram, the position locates the image on the screen, and the size of the rectangle and the size and shape of the parallelogram determines the scaling and shearing of the drawn image.

Private Sub DrawImageParaRectAttrib(ByVal e As PaintEventArgs)

    ' Create image.
    Dim newImage As Image = Image.FromFile("SampImag.jpg")

    ' Create parallelogram for drawing image.
    Dim ulCorner1 As New Point(100, 100)
    Dim urCorner1 As New Point(325, 100)
    Dim llCorner1 As New Point(150, 250)
    Dim destPara1 As Point() = {ulCorner1, urCorner1, llCorner1}

    ' Create rectangle for source image.
    Dim srcRect As New Rectangle(50, 50, 150, 150)
    Dim units As GraphicsUnit = GraphicsUnit.Pixel

    ' Draw original image to screen.
    e.Graphics.DrawImage(newImage, destPara1, srcRect, units)

    ' Create parallelogram for drawing adjusted image.
    Dim ulCorner2 As New Point(325, 100)
    Dim urCorner2 As New Point(550, 100)
    Dim llCorner2 As New Point(375, 250)
    Dim destPara2 As Point() = {ulCorner2, urCorner2, llCorner2}

    ' Create image attributes and set large gamma.
    Dim imageAttr As New ImageAttributes
    imageAttr.SetGamma(4.0F)

    ' Draw adjusted image to screen.
    e.Graphics.DrawImage(newImage, destPara2, srcRect, units, _
    imageAttr)
End Sub

.NET Framework
Available since 1.1
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