Miscellaneous Graphics Class Methods in GDI+

This article has been excerpted from book "Graphics Programming with GDI+".

The Graphics class provides more than just draw and fill methods. Miscellaneous methods are defined in Table 3.6. Some of these methods are discussed in more detail later.

The Clear Method

The Clear method clears the entire drawing surface and fills it with the specified background color. It takes one argument, of type Color. To clear a form, an application passes the form's background color. The following code snippet uses the Clear method to clear a form.

            form.Graphics g = this.CreateGraphics();
            g.Clear(this.BackColor);
            g.Dispose();



FIGURE 3.39: Filling a polygon

FIGURE 3.40: Filling rectangle

TABLE 3.6: Some miscellaneous Graphics methods

Methods	Description
AddMetafileComment	Adds a comment to a Metafile object.
Clear	Clears the entire drawing surface and fills it with the specified background color.
ExcludeClip	Updates the clip region to exclude the area specified by a Rectangle structure.
Flush	Forces execution of all pending graphics operations and returns immediate without waiting for the operations to finish.
FromHdc	Create a new Graphics object from a device context handle.
FromHwnd	Creates a new Graphics object from a window handle.
FromImage	Creates a new Graphics object from an Image object.
GetHalftonePalette	Returns a handle to the current Windows halftone palette.
GetHdc	Returns the device context handle associated with a Graphics object.
GetNearestColor	Returns the nearest color to the specified Color structure.
IntersectClip	Updates the clip region of a Graphics object to the intersection of the current clip region and a Rectangle structure.
IsVisible	Returns true if a point is within the visible clip region.
MeasureCharacterRanges	Returns an array of Region objects, each of which bounds a range of character positions within a string.
MeaureString	Measures a string when drawn with the specified Font object.
MultiplyTransform	Multiplies the world transformation and the Matrix object.
ReleaseHdc	Release a device context handle obtained by a previous call to the GetHdc method.
ResetClip	Resets the clip region to an infinite region.
ResetTransform	Resets the world transformation matrix to the identity matrix.
Restore	Restores the state of a Graphics object to the state represented by a GraphicsState object. Takes GraphicsState as input, removes the information block from the stack, and restores the Graphics object to the state it was in when it was saved.
RotateTransform	Applies rotation to the transformation matrix.
Save	Saves the information block of a Graphics object. The information block stores the state of the Graphics object. The Save method returns a GraphicsState object that identifies the information block.
ScaleTransform	Applied the specified scaling operation to the transformation matrix.
SetClip	Sets the clipping region to the Clip property.
TransformPoints	Transforms an array of points from one coordinate space to another using the current world and page transformations.
TranslateClip	Translates the clipping region by specified amounts in the horizontal and vertical directions.
TranslateTransform	Prepares the specified translation to the transformation matrix.

Conclusion

Hope the article would have helped you in understanding Miscellaneous Graphics Class Methods in GDI+. Read other articles on GDI+ on the website.

This book teaches .NET developers how to work with GDI+ as they develop applications that include graphics, or that interact with monitors or printers. It begins by explaining the difference between GDI and GDI+, and covering the basic concepts of graphics programming in Windows.