GDI+ Fonts

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1. How do I set the font for a control?
2. When I try to set a particular font style, say italics, I get an error message "Property cannot be assigned to -- it is read only". How can I set this read only property?
3. How can I draw font samples from the available fonts?
4. MeasureString seems to have problems with white space and punctuation. Is there a better method to use?
5. How can I draw a single line of text with different fonts using DrawString?
6. How do I display adjacent text?
7. How can I fill a combobox with available fonts?
 

1 How do I set the font for a control?

Use the Font property for the control along with the Font class in the System.Drawing class.

     button1.Font = new Font ("Courier", 10, FontStyle.Bold);
 

2 When I try to set a particular font style, say italics, I get an error message "Property cannot be assigned to -- it is read only". How can I set this read only property?

Code such as

     tabControl1.Font.Italic = true;

will not work. Instead, you have to create a new Font object, and set the property during its creation. This code will work.

     tabControl1.Font = new Font(tabControl1.Font, FontStyle.Italic);
 

3 How can I draw font samples from the available fonts?

James DeBroeck of Microsoft gave this response on the microsoft.public.dotnet.framework.windowsforms.

Here is some C# OnPaint code that will show you how to use FontFamily to get a list of fonts:

protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)
{
int i, nCount;
SolidBrush b = new SolidBrush( Color.Black );
int x = 0, y = 0;
nCount = FontFamily.Families.Length;

for(i=0;i
{
FontStyle fs = FontStyle.Regular;
Font f;
String StylesDesc = "";
if (FontFamily.Families[i].IsStyleAvailable(FontStyle.Regular))
     StylesDesc += "Regular ";
else
     fs = FontStyle.Italic;
if (FontFamily.Families[i].IsStyleAvailable(FontStyle.Italic))
     StylesDesc += "Italic ";
else
     fs = FontStyle.Bold;
if (FontFamily.Families[i].IsStyleAvailable(FontStyle.Bold))
     StylesDesc += "Bold ";
if (FontFamily.Families[i].IsStyleAvailable(FontStyle.Underline))
     StylesDesc += "Underline ";
if (FontFamily.Families[i].IsStyleAvailable(FontStyle.Strikeout))
     StylesDesc += "Strikeout ";
if (StylesDesc.Length > 0)
     StylesDesc = StylesDesc.Substring(0,StylesDesc.Length-1);
f = new Font( FontFamily.Families[i].Name, 12, fs);
String s = FontFamily.Families[i].Name + " " + StylesDesc;
e.Graphics.DrawString( s, f, b, x, y );
y += f.Height;
}
}
 

4 MeasureString seems to have problems with white space and punctuation. Is there a better method to use?

Try calling one of the overloads of MeasureString that takes an StringFormat parameter and pass it StringFormat.GenericTypographic. Here is some code that shows the same string and font giving different results depending upon the StringFormat parameter.

StringFormat sf = new StringFormat(StringFormat.GenericTypographic);
SizeF size = e.Graphics.MeasureString("this has some words", Font, 500, sf);
SizeF size1 = e.Graphics.MeasureString("this has some words", Font);
string s = string.Format("GenericTypographic={0:f2} GenericDefault={1:f2}", size.Width, size1.Width);
MessageBox.Show(s);
 

5 How can I draw a single line of text with different fonts using DrawString?

The key is that you have to calculate the ascent height of the font. The font ascent as reported by FontFamily.GetCellAscent is in what is called 'Design Units'. The Cell Spacing design unit value of fonts is proportional to the actual height of the font on the device. We use this relationship to calculate cell ascent in device units.
The rendering code has to just ensure that the x, y position passed to DrawString takes care of the ascent.

     private void HandlePaint(object sender, PaintEventArgs args)
     {
          // clear the background
          Graphics g = args.Graphics;
          g.Clear(Color.AliceBlue);

          // create a pen
          Pen pen = new Pen(Color.Red, 1f);

          // the string to be drawn
          string s = "Side by side";

          // the first font
          Font f1 = new Font("Arial", 10f);
          float strWidth1 = g.MeasureString(s, f1).Width;
          float fontHeight1 = f1.GetHeight(g);
          float fontAscentHeight1 = (fontHeight1/f1.FontFamily.GetLineSpacing(f1.Style))*f1.FontFamily.GetCellAscent(f1.Style);

          // the second font
          Font f2 = new Font("Times New Roman", 48);
               float fontHeight2 = f2.GetHeight(g);
               float fontAscentHeight2 = (fontHeight2/f2.FontFamily.GetLineSpacing(f2.Style))*f2.FontFamily.GetCellAscent(f2.Style);

          // draw the base line
          Point ptStart = new Point(0, this.ClientSize.Height/2);
          Point ptEnd = new Point(this.ClientSize.Width, this.ClientSize.Height/2);
          g.DrawLine(Pens.Black, ptStart, ptEnd);

          // draw string with first font
          g.DrawString(s, f1, Brushes.Red, new PointF(0, ptStart.Y - fontAscentHeight1));
          // draw string with second font
          g.DrawString(s, f2, Brushes.Red, new PointF(strWidth1, ptStart.Y - fontAscentHeight2));
     }
 

6 How do I display adjacent text?

Check out this article by David C. Browm of the Windows Forms team at gotnetdot.com. It discusses several reasons why you GDI+ output may lok differently that GDI output. One of the topics discussed is how to draw adjacent text.
 

7 How can I fill a combobox with available fonts?

Try

     comboBox1.Items.AddRange(FontFamily.Families);