public static SizeF MeasureText(Graphics g, string text, Font font)
{
// Due to the way the TextBox currently works, it measures each
// character one at a time. And it does this alot. So here we
// are implementing a cache for each font/character combination
// measurement. Since the number of fonts and number of characters
// used tends to be small, this is a good performance gain for
// not too much memory.
if (text.Length == 1)
{
// If g.VisibleClipBounds is {X=0, Y=0, Width=1, Height=1}, then some characters
// (in some fonts for some point sizes) return a different width then when the
// VisibleClipBounds has a different (usually but not always more reasonable) value.
// This state of the Graphics object can occur during initialization of text boxes
// with preset Text values. See https://bugzilla.xamarin.com/show_bug.cgi?id=26258
// for more details.
string sep;
var bounds = g.VisibleClipBounds;
if (bounds.Width == 1 && bounds.Height == 1 && bounds.X == 0 && bounds.Y == 0)
{
sep = "-1x1|";
}
else
{
sep = "|";
}
string key = font.GetHashCode().ToString() + sep + text;
if (measure_cache.ContainsKey(key))
{
return((SizeF)measure_cache[key]);
}
else
{
SizeF size;
if (!use_textrenderer)
{
size = g.MeasureString(text, font, 10000, sf_nonprinting);
}
else
{
size = TextRenderer.MeasureTextInternal(g, text, font, Size.Empty, TextFormatFlags.NoPadding | TextFormatFlags.NoPrefix, false);
}
measure_cache[key] = size;
return(size);
}
}
if (!use_textrenderer)
{
return(g.MeasureString(text, font, 10000, sf_nonprinting));
}
else
{
return(TextRenderer.MeasureTextInternal(g, text, font, Size.Empty, TextFormatFlags.NoPadding | TextFormatFlags.NoPrefix, false));
}
}
public static SizeF MeasureText(Graphics g, string text, Font font)
{
// Due to the way the TextBox currently works, it measures each
// character one at a time. And it does this alot. So here we
// are implementing a cache for each font/character combination
// measurement. Since the number of fonts and number of characters
// used tends to be small, this is a good performance gain for
// not too much memory.
if (text.Length == 1)
{
string key = font.GetHashCode().ToString() + "|" + text;
if (measure_cache.ContainsKey(key))
{
return((SizeF)measure_cache[key]);
}
else
{
SizeF size;
if (!use_textrenderer)
{
size = g.MeasureString(text, font, 10000, sf_nonprinting);
}
else
{
size = TextRenderer.MeasureTextInternal(g, text, font, Size.Empty, TextFormatFlags.NoPadding | TextFormatFlags.NoPrefix, false);
}
measure_cache[key] = size;
return(size);
}
}
if (!use_textrenderer)
{
return(g.MeasureString(text, font, 10000, sf_nonprinting));
}
else
{
return(TextRenderer.MeasureTextInternal(g, text, font, Size.Empty, TextFormatFlags.NoPadding | TextFormatFlags.NoPrefix, false));
}
}
