/// <summary>
/// Provides the size, in pixels, of the specified text.
/// </summary>
/// <param name="dc">The device context in which to measure the text.</param>
/// <param name="text">The text to measure.</param>
/// <param name="font">The <see cref="Font"/> to apply to the measured text.</param>
/// <param name="textFormat">A bitwise combination of the <see cref="TextFormatFlags" /> values.</param>
/// <returns>The <see cref="Size"/>, in pixels, of <paramref name="text"/> drawn with the specified <paramref name="font"/> and format.</returns>
/// <exception cref="NotSupportedException">The current operating system does not support glass, or the Desktop Window Manager is not enabled.</exception>
/// <exception cref="ArgumentNullException"><paramref name="dc"/>, <paramref name="text"/> or <paramref name="font"/> is <see langword="null"/>.</exception>
public static Size MeasureCompositedText(IDeviceContext dc, string text, Font font, TextFormatFlags textFormat)
{
if (!IsDwmCompositionEnabled)
{
throw new NotSupportedException(Properties.Resources.GlassNotSupportedError);
}
if (dc == null)
{
throw new ArgumentNullException("dc");
}
if (text == null)
{
throw new ArgumentNullException("text");
}
if (font == null)
{
throw new ArgumentNullException("font");
}
IntPtr primaryHdc = dc.GetHdc();
try
{
Rectangle bounds = new Rectangle(0, 0, int.MaxValue, int.MaxValue);
using (SafeDeviceHandle memoryHdc = NativeMethods.CreateCompatibleDC(primaryHdc))
using (SafeGDIHandle fontHandle = new SafeGDIHandle(font.ToHfont(), true))
using (SafeGDIHandle dib = NativeMethods.CreateDib(bounds, primaryHdc, memoryHdc))
{
NativeMethods.SelectObject(memoryHdc, fontHandle);
System.Windows.Forms.VisualStyles.VisualStyleRenderer renderer = new System.Windows.Forms.VisualStyles.VisualStyleRenderer(System.Windows.Forms.VisualStyles.VisualStyleElement.Window.Caption.Active);
NativeMethods.RECT bounds2 = new NativeMethods.RECT(bounds);
NativeMethods.RECT rect;
NativeMethods.GetThemeTextExtent(renderer.Handle, memoryHdc, 0, 0, text, text.Length, (int)textFormat, ref bounds2, out rect);
return(new Size(rect.Right - rect.Left, rect.Bottom - rect.Top));
}
}
finally
{
dc.ReleaseHdc();
}
}
public static extern IntPtr SelectObject(SafeDeviceHandle hDC, SafeGDIHandle hObject);