C# 4 and .NET 4

OC28 ❘ ChaPTer 48 GrAphics with Gdi+
Figure 48 - 15 shows the result of running this example.
The example demonstrates the use of the Graphics.DrawString()
method to draw items of text. The method DrawString() comes in
a number of overloads, three of which are demonstrated here. The
different overloads require parameters that indicate the text to be
displayed, the font that the string should be drawn in, and the brush
that should be used to construct the various lines and curves that make
up each character of text. A few alternatives exist for the remaining
parameters. In general, however, it is possible to specify either a Point
(or equivalently, two numbers) or a Rectangle .
If you specify a Point , then the text will start with its top - left corner
at that Point and simply stretch out to the right. If you specify a
Rectangle , then the Graphics instance will lay out the string inside
figure 48-15
that rectangle. If the text does not fi t within the boundaries of the
rectangle, it will be cut off (see the fourth line of text in Figure 48 - 15). Passing a rectangle to DrawString()
means that the drawing process will take longer because DrawString() will need to fi gure out where to put
line breaks, but the result may look nicer — provided the string fi ts in the rectangle!
This example also shows a few ways to construct fonts. You always need to include the name of the font and
its size (height). You can also optionally pass in various styles that modify how the text is to be drawn (bold,
underline, and so on).
fonTs and fonT families
A font describes exactly how each letter should be displayed. Selection of the appropriate font and providing
a reasonable variety of fonts within a document are important factors in improving readability.
Most people, if asked to name a font, might mention Arial or Times New Roman (if they are Windows
users) or Times or Helvetica (if they are Mac OS users). In fact, these are not fonts at all — they are font
families. The font family tells you, in generic terms, the visual style of the text and is a key factor in the
overall appearance of your application. Most of us recognize the styles of the most common font families,
even if we are not consciously aware of it.
An actual font would be something like Arial 9 - point italic. In other words, the size and other modifi cations
to the text are specifi ed as well as the font family. These modifi cations might include whether text is
bold , italic, underlined, or displayed in small caps or as subscript
; this is technically referred to as the style,
although in some ways, the term is misleading because the visual appearance is determined as much by the
font family.
The size of the text is measured by specifying its height. The height is measured in points — a traditional
unit that represents 1 / 72 of an inch (0.351 mm). So letters in a 10 - point font are roughly 1 / 7 of an inch,
or 3.5 mm high. However, you will not get seven lines of 10 - point text into one inch of vertical screen or
paper space, as you need to allow for the spacing between the lines as well.
Strictly speaking, measuring the height is not quite as simple as that because there are
several different heights that you must consider. For example, there is the height of tall
letters such as the A or F (this is the measurement that we are referring to when we talk
about the height), the additional height occupied by any accents on letters such as Å or
Ñ (the internal leading), and the extra height below the baseline needed for the tails of
letters such as y and g (the descent). However, for this chapter we will not worry about
that. When you specify the font family and the main height, these subsidiary heights are
determined automatically.
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