基于@brgerner 提供的article,我将在此处提供替代实现,因为标记为答案的实现不如下面的那么高效也不完整:
public class FontWizard
{
public static Font FlexFont(Graphics g, float minFontSize, float maxFontSize, Size layoutSize, string s, Font f, out SizeF extent)
{
if (maxFontSize == minFontSize)
f = new Font(f.FontFamily, minFontSize, f.Style);
extent = g.MeasureString(s, f);
if (maxFontSize <= minFontSize)
return f;
float hRatio = layoutSize.Height / extent.Height;
float wRatio = layoutSize.Width / extent.Width;
float ratio = (hRatio < wRatio) ? hRatio : wRatio;
float newSize = f.Size * ratio;
if (newSize < minFontSize)
newSize = minFontSize;
else if (newSize > maxFontSize)
newSize = maxFontSize;
f = new Font(f.FontFamily, newSize, f.Style);
extent = g.MeasureString(s, f);
return f;
}
public static void OnPaint(object sender, PaintEventArgs e, string text)
{
var control = sender as Control;
if (control == null)
return;
control.Text = string.Empty; //delete old stuff
var rectangle = control.ClientRectangle;
using (Font f = new System.Drawing.Font("Microsoft Sans Serif", 20.25f, FontStyle.Bold))
{
SizeF size;
using (Font f2 = FontWizard.FlexFont(e.Graphics, 5, 50, rectangle.Size, text, f, out size))
{
PointF p = new PointF((rectangle.Width - size.Width) / 2, (rectangle.Height - size.Height) / 2);
e.Graphics.DrawString(text, f2, Brushes.Black, p);
}
}
}
}
及用法:
val label = new Label();
label.Paint += (sender, e) => FontWizard.OnPaint(sender, e, text);