The Font Class in GDI+

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

The font class combines a font and methods and properties to define functionalities such as a font size, style, name and conversion. Table 5.8 describes the properties of the Font class.

The Following code creates a font object of font family Arial with size 16 and uses the Font class properties to find out the details of the Font object.

Font arialFont = new Font (" Arial ", 16, FontStyle.Bold|FontStyle.Underline|FontStyle.Italic);

MessageBox.Show(" Font Properties = Name: " + arialFont.Name + " Size: " + arialFont.Size.ToString() + " Style :"+ arialFont.Style.ToString() + " Default Unit:" + arialFont.Unit.ToString() + "Size in points:"+ arialFont.SizeInPoints.ToString());

The Font class provide three static methods: FromHdc, FromHfont, and FromLogFont. These methods create a Font object from a window handle to a device context, a window handle and GDI LOGFONT structure, respectively. The GetHeight method returns the height of a Font object. The ToHfont and ToLogFont methods convert a Font object to window handler and GDI LOGFONT structure, respectively.

TABLE 5.8 Font properties

Property	Description
Bold	Return true if the font is bold.
FontFamily	Every font belongs to s font family. This property return the FontFamily object associated with a Font object.
GdiCharSet	Return a string containing all characters.
GdiVerticalFont	Returns true if a font is derived from a GDI vertical font; Otherwise return false.
Height	Return the height of a font.
Italic	Return true if font is italic.
Name	Return the face name off font.
Size	Return the em size of a font in font design units.
SizeInPoints	Return size, in points of a font.
Strickout	Return true if a font specifies a horizontal line through the font.
Style	Return style information for a font, which is a type FontStyle enumeration.
Underline	Return true if font is underlined.
Unit	Return the unit of measure for a font.

In the following example, you must import the GDI library by adding the following code at the beginning of your class before using any GDI fonts, because we will be using GetStockObject:

[System.Runtime.InteropServices.DllImportAttribute("gdi32.dll")]

private static extern IntPtrn GetStockobject(int fnobj);

Listing 5.7 creates a font from a GDI handle and draws a string on the form. The FromHfont method creates a Font object from a GDI handle.

LISTING 5.7 Using the FromHfont method 

private   void FromHfontmenu_Click(object sender, System.EventArgs e)

{

      //Create the Graphics object

     Graphics  g  = this.CreateGraphics();

      //Create a brush

     SolidBrush brush = new SolidBrush(Color.Red);

      //Get a handle    

     Intptr hFont = GetStockobject(o);

      //Create a font from the handle A 

     Font hfontFont = Font.FromHfont(hfont);

      //Draw text

     g.DrawString("GDI HFONT",hfontFont,brush,20,20);

      //Dipose of objects

     hfontFont.Dispose();

     g.Dispose();

}

Figure 5.12 shows the output from Listing 5.7

FIGURE 5.12 Using the FromHFont method

Conclusion

Hope the article would have helped you in understanding Font Class 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.