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

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

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

public void DrawImage (
	Image image,
	Rectangle destRect,
	float srcX,
	float srcY,
	float srcWidth,
	float srcHeight,
	GraphicsUnit srcUnit,
	ImageAttributes imageAttrs,
	DrawImageAbort callback,
	IntPtr callbackData
)
public void DrawImage (
	Image image, 
	Rectangle destRect, 
	float srcX, 
	float srcY, 
	float srcWidth, 
	float srcHeight, 
	GraphicsUnit srcUnit, 
	ImageAttributes imageAttrs, 
	DrawImageAbort callback, 
	IntPtr callbackData
)
public function DrawImage (
	image : Image, 
	destRect : Rectangle, 
	srcX : float, 
	srcY : float, 
	srcWidth : float, 
	srcHeight : float, 
	srcUnit : GraphicsUnit, 
	imageAttrs : ImageAttributes, 
	callback : DrawImageAbort, 
	callbackData : IntPtr
)
Not applicable.

Parameters

image

Image to draw.

destRect

Rectangle structure that specifies the location and size of the drawn image. The image is scaled to fit the rectangle.

srcX

The x-coordinate of the upper-left corner of the portion of the source image to draw.

srcY

The 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.

imageAttrs

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

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.

callbackData

Value specifying additional data for the Graphics.DrawImageAbort delegate to use when checking whether to stop execution of the DrawImage method.

Exception typeCondition

ArgumentNullException

image is a null reference (Nothing in Visual Basic).

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 parameter.

This overload with the callback and callbackData parameters provides the means to stop the drawing of an image once it starts according to criteria and data 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.

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 first defines a callback method for the Graphics.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 Graphics.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.

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.

Because this example uses an overload that passes a callBackData parameter, the Graphics.DrawImageAbort callback returns false, which causes the DrawImage method to continue, and the example draws the adjusted image to the screen.


// Define DrawImageAbort callback method.
private bool DrawImageCallback8(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 DrawImageRect4FloatAttribAbortData(PaintEventArgs e)
{
             
    // Create callback method.
    Graphics.DrawImageAbort imageCallback
        = new Graphics.DrawImageAbort(DrawImageCallback8);
    IntPtr imageCallbackData = new IntPtr(1);
             
    // 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.
    float x = 50.0F;
    float y = 50.0F;
    float width = 150.0F;
    float height = 150.0F;
    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);
             
    // Draw adjusted image to screen.
    try
    {
        checked
        {
             
            // Draw adjusted image to screen.
            e.Graphics.DrawImage(
                newImage,
                destRect2,
                x, y,
                width, height,
                units,
                imageAttr,
                imageCallback,
                imageCallbackData);
        }
    }
    catch (Exception ex)
    {
        e.Graphics.DrawString(
            ex.ToString(),
            new Font("Arial", 8),
            Brushes.Black,
            new PointF(0, 0));
    }
}

// Define DrawImageAbort callback method.
private boolean DrawImageCallback8(IntPtr callBackData) 
{    
    // Test for call that passes callBackData parameter.
    if (callBackData.Equals( IntPtr.Zero)) { 
        // If no callBackData passed, abort DrawImage method.
        return true ;
    }
    else {
        // If callBackData passed, continue DrawImage method.
        return false ;
    }
} //DrawImageCallback8

public void DrawImageRect4FloatAttribAbortData(PaintEventArgs e) 
{ 
    // Create callback method.
    Graphics.DrawImageAbort imageCallback =  new Graphics.DrawImageAbort(
        DrawImageCallback8);
    IntPtr imageCallbackData =  new IntPtr(1);

    // 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.
    float x = 50;
    float y = 50;
    float width = 150;
    float height = 150;
    GraphicsUnit units = GraphicsUnit.Pixel;

    // Draw original image to screen.
    e.get_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);

    try {
            // Draw adjusted image to screen.
        e.get_Graphics().DrawImage(newImage, destRect2, x, y, width,
            height, units, imageAttr, imageCallback, imageCallbackData);
    }
    catch(System.Exception  ex) {    
        e.get_Graphics().DrawString(ex.ToString(), new Font("Arial", 8), 
            Brushes.get_Black(), new PointF(0, 0));
    }
} //DrawImageRect4FloatAttribAbortData

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0
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