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Graphics.DrawImage Method (Image, Rectangle, Int32, Int32, Int32, Int32, GraphicsUnit, ImageAttributes, Graphics.DrawImageAbort)

.NET Framework 1.1

Draws the specified portion of the specified Image object at the specified location and with the specified size.

[Visual Basic]
Overloads Public Sub DrawImage( _
   ByVal image As Image, _
   ByVal destRect As Rectangle, _
   ByVal srcX As Integer, _
   ByVal srcY As Integer, _
   ByVal srcWidth As Integer, _
   ByVal srcHeight As Integer, _
   ByVal srcUnit As GraphicsUnit, _
   ByVal imageAttr As ImageAttributes, _
   ByVal callback As Graphics.DrawImageAbort _
)
[C#]
public void DrawImage(
 Image image,
 Rectangle destRect,
 int srcX,
 int srcY,
 int srcWidth,
 int srcHeight,
 GraphicsUnit srcUnit,
 ImageAttributes imageAttr,
 Graphics.DrawImageAbort callback
);
[C++]
public: void DrawImage(
 Image* image,
 Rectangle destRect,
 int srcX,
 int srcY,
 int srcWidth,
 int srcHeight,
 GraphicsUnit srcUnit,
 ImageAttributes* imageAttr,
 Graphics.DrawImageAbort* callback
);
[JScript]
public function DrawImage(
   image : Image,
 destRect : Rectangle,
 srcX : int,
 srcY : int,
 srcWidth : int,
 srcHeight : int,
 srcUnit : GraphicsUnit,
 imageAttr : ImageAttributes,
 callback : Graphics.DrawImageAbort
);

Parameters

image
Image object to draw.
destRect
Rectangle structure that specifies the location and size of the drawn image. The image is scaled to fit the rectangle.
srcX
x-coordinate of the upper-left corner of the portion of the source image to draw.
srcY
y-coordinate of the upper-left corner of the portion of the source image to draw.
srcWidth
Width of the portion of the source image to draw.
srcHeight
Height of the portion of the source image to draw.
srcUnit
Member of the GraphicsUnit enumeration that specifies the units of measure used to determine the source rectangle.
imageAttr
ImageAttributes object that specifies recoloring and gamma information for image.
callback
Graphics.DrawImageAbort delegate that specifies a method to call during the drawing of the image. This method is called frequently to check whether to stop execution of the DrawImage method according to application-determined criteria.

Return Value

This method does not return a value.

Remarks

The srcX, srcY, srcWidth, and srcHeight parameters specify a rectangular portion, of the image object to draw. The rectangle is relative to the upper-left corner of the source image. This portion is scaled to fit inside the rectangle specified by the destRect object.

This overload with the callback parameter provides the means to stop the drawing of an image once it starts according to criteria determined by the application. For example, an application could start drawing a large image and the user might scroll the image off the screen, in which case the application could stop the drawing.

Example

[Visual Basic, C#] The following example is designed for use with Windows Forms, and it requires PaintEventArgs e, which is a parameter of the Paint event handler. The code first defines a callback method for the DrawImageAbort delegate; the definition is simplistic and merely tests to see whether the DrawImage method calls it with a null callBackData parameter. The main body of the example performs the following actions:

  • Creates an instance of the DrawImageAbort callback method.
  • Creates an image from a JPEG file SampImag.jpg in the folder of the example.
  • Creates points that define a destination rectangle in which to draw the image.
  • Creates a source 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 destination rectangle 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.

[Visual Basic, C#] For the original, unadjusted destination rectangle, the position locates the image on the screen, and the size of the source rectangle and the size and shape of the destination rectangle determines the scaling of the drawn image.

[Visual Basic, C#] Because this example uses an overload that does not pass a callBackData parameter, the DrawImageAbort callback returns true, which causes the DrawImage method to abort, and the exception-handling code included in the example prints out the exception text rather than drawing the image.

[Visual Basic] 
Private Function DrawImageCallback(callBackData As IntPtr) As Boolean
' Test for call that passes callBackData parameter.
If callBackData.Equals(IntPtr.Zero) Then
' If no callBackData passed, abort DrawImage method.
Return True
Else
' If callBackData passed, continue DrawImage method.
Return False
End If
End Function
Public Sub DrawImageRect4IntAtrribAbort(e As PaintEventArgs)
' Create callback method.
Dim imageCallback As New _
Graphics.DrawImageAbort(AddressOf DrawImageCallback)
' Create image.
Dim newImage As Image = Image.FromFile("SampImag.jpg")
' Create rectangle for displaying original image.
Dim destRect1 As New Rectangle(100, 25, 450, 150)
' Create coordinates of rectangle for source image.
Dim x As Integer = 50
Dim y As Integer = 50
Dim width As Integer = 150
Dim height As Integer = 150
Dim units As GraphicsUnit = GraphicsUnit.Pixel
' Draw original image to screen.
e.Graphics.DrawImage(newImage, destRect1, x, y, width, height, _
units)
' Create rectangle for adjusted image.
Dim destRect2 As New Rectangle(100, 175, 450, 150)
' Create image attributes and set large gamma.
Dim imageAttr As New ImageAttributes()
imageAttr.SetGamma(4F)
Try
' Draw adjusted image to screen.
e.Graphics.DrawImage(newImage, destRect2, x, y, width, _
height, units, imageAttr, imageCallback)
Catch ex As Exception
e.Graphics.DrawString(ex.ToString(), New Font("Arial", 8), _
Brushes.Black, New PointF(0, 0))
End Try
End Sub
        
[C#] 
// Define DrawImageAbort callback method.
private bool DrawImageCallback(IntPtr callBackData)
{
// Test for call that passes callBackData parameter.
if(callBackData==IntPtr.Zero)
{
// If no callBackData passed, abort DrawImage method.
return true;
}
else
{
// If callBackData passed, continue DrawImage method.
return false;
}
}
public void DrawImageRect4IntAtrribAbort(PaintEventArgs e)
{
// Create callback method.
Graphics.DrawImageAbort imageCallback
= new Graphics.DrawImageAbort(DrawImageCallback);
// Create image.
Image newImage = Image.FromFile("SampImag.jpg");
// Create rectangle for displaying original image.
Rectangle destRect1 = new Rectangle(100, 25, 450, 150);
// Create coordinates of rectangle for source image.
int x = 50;
int y = 50;
int width = 150;
int height = 150;
GraphicsUnit units = GraphicsUnit.Pixel;
// Draw original image to screen.
e.Graphics.DrawImage(newImage, destRect1, x, y, width, height, units);
// Create rectangle for adjusted image.
Rectangle destRect2 = new Rectangle(100, 175, 450, 150);
// Create image attributes and set large gamma.
ImageAttributes imageAttr = new ImageAttributes();
imageAttr.SetGamma(4.0F);
try
{
checked
{
// Draw adjusted image to screen.
e.Graphics.DrawImage(
newImage,
destRect2,
x, y,
width, height,
units,
imageAttr,
imageCallback);
}
}
catch (Exception ex)
{
e.Graphics.DrawString(
ex.ToString(),
new Font("Arial", 8),
Brushes.Black,
new PointF(0, 0));
}
}
        

[C++, JScript] No example is available for C++ or JScript. To view a Visual Basic or C# example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also

Graphics Class | Graphics Members | System.Drawing Namespace | Graphics.DrawImage Overload List

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