Name
Bitmap
Synopsis
This subclass of Image
encapsulates a picture
represented by a 2D array of pixel data. It supports a range of
PixelFormat
s, including both true-color and
palette-color bitmaps, and those with an alpha channel for
transparency.
A Bitmap
conceptually represents a system bitmap
and is ultimately implemented through a native GDI+ bitmap handle. As
with most drawing classes that wrap limited resources
(Pen
and Brush
being other
examples), you should have a well-defined lifetime management plan,
calling Dispose()
when you are finished to
release the resources back to the system (the
using
idiom in C# is useful here: see the main
body of the text for details). If you rely on the garbage collector
to do this, the Bitmap
object will be collected
but its pixel data will be leaked until the garbage collector happens
to run, which may be too late.
There are several ways to construct a Bitmap
object. One of the most is common is to provide the filename of the
picture that you want to load. The framework will use the installed
CODECs (BMP, PNG, JPG, and GIF) to attempt to load the image. Note
that the file itself will remain locked until the
Bitmap
that loaded it is disposed. However, you
can Clone()
the bitmap and Dispose()
the original to release the file.
Alternatively, you can construct bitmaps of a specific size and
PixelFormat
, or bitmaps compatible with a
particular Graphics
surface. You can also
construct from another Image
(optionally rescaling the original in the process), ...
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