/// GetTextMargins - checks to see if we have cached information about the current font,
/// returns info about it.
/// An MRU of Font margins was considered, but seems like overhead.
internal static Interop.User32.DRAWTEXTPARAMS GetTextMargins(WindowsGraphics wg, WindowsFont font)
{
// PERF: operate on a local reference rather than party directly on the thread static one.
CachedInfo currentCachedInfo = cachedMeasurementDCInfo;
if (currentCachedInfo != null && currentCachedInfo.LeftTextMargin > 0 && currentCachedInfo.RightTextMargin > 0 && font == currentCachedInfo.LastUsedFont)
{
// we have to return clones as DrawTextEx will modify this struct
return(new Interop.User32.DRAWTEXTPARAMS
{
iLeftMargin = currentCachedInfo.LeftTextMargin,
iRightMargin = currentCachedInfo.RightTextMargin
});
}
else if (currentCachedInfo == null)
{
currentCachedInfo = new CachedInfo();
cachedMeasurementDCInfo = currentCachedInfo;
}
Interop.User32.DRAWTEXTPARAMS drawTextParams = wg.GetTextMargins(font);
currentCachedInfo.LeftTextMargin = drawTextParams.iLeftMargin;
currentCachedInfo.RightTextMargin = drawTextParams.iRightMargin;
// returning a copy here to be consistent with the return value from the cache.
return(new Interop.User32.DRAWTEXTPARAMS
{
iLeftMargin = currentCachedInfo.LeftTextMargin,
iRightMargin = currentCachedInfo.RightTextMargin
});
}
private int GetLeadingTextPaddingFromTextFormatFlags()
{
int iLeftMargin;
if (!base.IsHandleCreated)
{
return(0);
}
if (this.UseCompatibleTextRendering && (this.FlatStyle != System.Windows.Forms.FlatStyle.System))
{
return(0);
}
using (WindowsGraphics graphics = WindowsGraphics.FromHwnd(base.Handle))
{
TextFormatFlags flags = this.CreateTextFormatFlags();
if ((flags & TextFormatFlags.NoPadding) == TextFormatFlags.NoPadding)
{
graphics.TextPadding = TextPaddingOptions.NoPadding;
}
else if ((flags & TextFormatFlags.LeftAndRightPadding) == TextFormatFlags.LeftAndRightPadding)
{
graphics.TextPadding = TextPaddingOptions.LeftAndRightPadding;
}
using (WindowsFont font = WindowsGraphicsCacheManager.GetWindowsFont(this.Font))
{
iLeftMargin = graphics.GetTextMargins(font).iLeftMargin;
}
}
return(iLeftMargin);
}
public void Font_GetTextMargins(string family, float size, int left, int right)
{
using Font font = new Font(family, size);
if (font.Name != family)
{
// Not installed on this machine
return;
}
using WindowsFont windowsFont = WindowsFont.FromFont(font, Gdi32.QUALITY.CLEARTYPE);
WindowsGraphics graphics = WindowsGraphicsCacheManager.MeasurementGraphics;
User32.DRAWTEXTPARAMS margins = graphics.GetTextMargins(windowsFont);
Assert.Equal(left, margins.iLeftMargin);
Assert.Equal(right, margins.iRightMargin);
}
/// GetTextMargins - checks to see if we have cached information about the current font,
/// returns info about it.
/// An MRU of Font margins was considered, but seems like overhead.
internal static IntNativeMethods.DRAWTEXTPARAMS GetTextMargins(WindowsGraphics wg, WindowsFont font) {
// PERF: operate on a local reference rather than party directly on the thread static one.
CachedInfo currentCachedInfo = cachedMeasurementDCInfo;
if (currentCachedInfo != null && currentCachedInfo.LeftTextMargin >0 && currentCachedInfo.RightTextMargin >0 && font == currentCachedInfo.LastUsedFont)
{
// we have to return clones as DrawTextEx will modify this struct
return new IntNativeMethods.DRAWTEXTPARAMS(currentCachedInfo.LeftTextMargin,currentCachedInfo.RightTextMargin);
}
else if (currentCachedInfo == null)
{
currentCachedInfo = new CachedInfo();
cachedMeasurementDCInfo = currentCachedInfo;
}
IntNativeMethods.DRAWTEXTPARAMS drawTextParams = wg.GetTextMargins(font);
currentCachedInfo.LeftTextMargin = drawTextParams.iLeftMargin;
currentCachedInfo.RightTextMargin = drawTextParams.iRightMargin;
// returning a copy here to be consistent with the return value from the cache.
return new IntNativeMethods.DRAWTEXTPARAMS(currentCachedInfo.LeftTextMargin,currentCachedInfo.RightTextMargin);
}
