mcs/class/Managed.Windows.Forms/System.Windows.Forms/TextRenderer.cs

   1 //
   2 // TextRenderer.cs
   3 //
   4 // Permission is hereby granted, free of charge, to any person obtaining
   5 // a copy of this software and associated documentation files (the
   6 // "Software"), to deal in the Software without restriction, including
   7 // without limitation the rights to use, copy, modify, merge, publish,
   8 // distribute, sublicense, and/or sell copies of the Software, and to
   9 // permit persons to whom the Software is furnished to do so, subject to
  10 // the following conditions:
  11 //
  12 // The above copyright notice and this permission notice shall be
  13 // included in all copies or substantial portions of the Software.
  14 //
  15 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  19 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  20 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  21 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  22 //
  23 // Copyright (c) 2006 Novell, Inc.
  24 //
  25 // Authors:
  26 //      Jonathan Pobst (monkey@jpobst.com)
  27 //
  28
  29 #if NET_2_0
  30 using System.Drawing;
  31 using System.Runtime.InteropServices;
  32 using System.Text;
  33 using System.Drawing.Text;
  34
  35 namespace System.Windows.Forms
  36 {
  37         public sealed class TextRenderer
  38         {
  39                 private TextRenderer ()
  40                 {
  41                 }
  42
  43                 #region Public Methods
  44                 [MonoTODO("This should be correct for Windows, other platforms need a more accurate fallback method than the one provided")]
  45                 public static void DrawText (IDeviceContext dc, string text, Font font, Rectangle bounds, Color foreColor, TextFormatFlags flags)
  46                 {
  47                         if (Environment.OSVersion.Platform == PlatformID.Win32NT || Environment.OSVersion.Platform == PlatformID.Win32Windows) {
  48                                 Rectangle new_bounds = bounds;
  49                                 new_bounds.Offset ((int)(dc as Graphics).Transform.OffsetX + 0, (int)(dc as Graphics).Transform.OffsetY + 0);
  50                                 IntPtr hdc = dc.GetHdc ();
  51
  52                                 SetTextColor (hdc, ColorTranslator.ToWin32 (foreColor));
  53                                 SetBkMode (hdc, 1);     //1-Transparent, 2-Opaque
  54
  55                                 VisualStyles.UXTheme.RECT r = VisualStyles.UXTheme.RECT.FromRectangle (new_bounds);
  56
  57                                 if (font != null)
  58                                         SelectObject (hdc, font.ToHfont ());
  59
  60                                 DrawText (hdc, text, text.Length, ref r, (int)flags);
  61                                 dc.ReleaseHdc ();
  62                         }
  63                         else {
  64                                 Graphics g;
  65
  66                                 if (dc is Graphics)
  67                                         g = (Graphics)dc;
  68                                 else
  69                                         g = Graphics.FromHdc (dc.GetHdc ());
  70
  71                                 StringFormat sf = FlagsToStringFormat (flags);
  72
  73                                 using (Brush b = new SolidBrush (foreColor))
  74                                         g.DrawString (text, font, b, bounds, sf);
  75
  76                                 if (!(dc is Graphics)) {
  77                                         g.Dispose ();
  78                                         dc.ReleaseHdc ();
  79                                 }
  80                         }
  81                 }
  82
  83                 [MonoTODO ("This should be correct for Windows, other platforms need a more accurate fallback method than the one provided")]
  84                 public static void DrawText (IDeviceContext dc, string text, Font font, Point pt, Color foreColor, TextFormatFlags flags)
  85                 {
  86                         if (Environment.OSVersion.Platform == PlatformID.Win32NT || Environment.OSVersion.Platform == PlatformID.Win32Windows) {
  87                                 IntPtr hdc = dc.GetHdc ();
  88
  89                                 SetTextColor (hdc, ColorTranslator.ToWin32 (foreColor));
  90                                 SetBkMode (hdc, 1);     //1-Transparent, 2-Opaque
  91
  92                                 Size sz = MeasureText(text, font);
  93
  94                                 VisualStyles.UXTheme.RECT r = new System.Windows.Forms.VisualStyles.UXTheme.RECT(pt.X, pt.Y, pt.X + sz.Width, pt.Y + sz.Height);
  95
  96                                 if (font != null)
  97                                         SelectObject (hdc, font.ToHfont ());
  98
  99                                 DrawText (hdc, text, text.Length, ref r, (int)flags);
 100                                 dc.ReleaseHdc ();
 101                         }
 102                         else {
 103                                 Graphics g;
 104
 105                                 if (dc is Graphics)
 106                                         g = (Graphics)dc;
 107                                 else
 108                                         g = Graphics.FromHdc (dc.GetHdc ());
 109
 110                                 StringFormat sf = FlagsToStringFormat (flags);
 111
 112                                 using (Brush b = new SolidBrush (foreColor))
 113                                         g.DrawString (text, font, b, pt, sf);
 114
 115                                 if (!(dc is Graphics)) {
 116                                         g.Dispose ();
 117                                         dc.ReleaseHdc ();
 118                                 }
 119                         }
 120                 }
 121
 122                 [MonoTODO ("This should be correct for Windows, other platforms need a more accurate fallback method than the one provided")]
 123                 public static Size MeasureText (string text, Font font)
 124                 {
 125                         if (Environment.OSVersion.Platform == PlatformID.Win32NT || Environment.OSVersion.Platform == PlatformID.Win32Windows) {
 126                                 Bitmap b = new Bitmap (5, 5);
 127                                 Graphics g = Graphics.FromImage (b);
 128
 129                                 IntPtr hdc = g.GetHdc ();
 130
 131                                 if (font != null)
 132                                         SelectObject (hdc, font.ToHfont ());
 133
 134                                 VisualStyles.UXTheme.SIZE text_size = new System.Windows.Forms.VisualStyles.UXTheme.SIZE();
 135
 136                                 GetTextExtentPoint32 (hdc, text, text.Length, out text_size);
 137
 138                                 g.ReleaseHdc();
 139
 140                                 Size retval = text_size.ToSize();
 141                                 //retval.Height += 4;
 142                                 if (retval.Width > 0) retval.Width += 6;
 143                                 return retval;
 144                         }
 145                         else {
 146                                 Bitmap b = new Bitmap (5, 5);
 147                                 Graphics g = Graphics.FromImage (b);
 148
 149                                 Size retval = g.MeasureString(text,font).ToSize();
 150                                 if (retval.Width > 0) retval.Width += 6;
 151                                 return retval;
 152                         }
 153                 }
 154                 #endregion
 155
 156                 #region Private Methods
 157                 private static StringFormat FlagsToStringFormat (TextFormatFlags flags)
 158                 {
 159                         StringFormat sf = new StringFormat ();
 160
 161                         // Translation table: http://msdn.microsoft.com/msdnmag/issues/06/03/TextRendering/default.aspx?fig=true#fig4
 162
 163                         // Horizontal Alignment
 164                         if ((flags & TextFormatFlags.HorizontalCenter) == TextFormatFlags.HorizontalCenter)
 165                                 sf.Alignment = StringAlignment.Center;
 166                         else if ((flags & TextFormatFlags.Right) == TextFormatFlags.Right)
 167                                 sf.Alignment = StringAlignment.Far;
 168                         else
 169                                 sf.Alignment = StringAlignment.Near;
 170
 171                         // Vertical Alignment
 172                         if ((flags & TextFormatFlags.Bottom) == TextFormatFlags.Bottom)
 173                                 sf.LineAlignment = StringAlignment.Far;
 174                         else if ((flags & TextFormatFlags.VerticalCenter) == TextFormatFlags.VerticalCenter)
 175                                 sf.LineAlignment = StringAlignment.Center;
 176                         else
 177                                 sf.LineAlignment = StringAlignment.Near;
 178
 179                         // Ellipsis
 180                         if ((flags & TextFormatFlags.EndEllipsis) == TextFormatFlags.EndEllipsis)
 181                                 sf.Trimming = StringTrimming.EllipsisCharacter;
 182                         else if ((flags & TextFormatFlags.PathEllipsis) == TextFormatFlags.PathEllipsis)
 183                                 sf.Trimming = StringTrimming.EllipsisPath;
 184                         else if ((flags & TextFormatFlags.WordEllipsis) == TextFormatFlags.WordEllipsis)
 185                                 sf.Trimming = StringTrimming.EllipsisWord;
 186                         else
 187                                 sf.Trimming = StringTrimming.Character;
 188
 189                         // Hotkey Prefix
 190                         if ((flags & TextFormatFlags.NoPrefix) == TextFormatFlags.NoPrefix)
 191                                 sf.HotkeyPrefix = HotkeyPrefix.None;
 192                         else if ((flags & TextFormatFlags.HidePrefix) == TextFormatFlags.HidePrefix)
 193                                 sf.HotkeyPrefix = HotkeyPrefix.Hide;
 194                         else
 195                                 sf.HotkeyPrefix = HotkeyPrefix.Show;
 196
 197                         // Text Padding
 198                         if ((flags & TextFormatFlags.NoPadding) == TextFormatFlags.NoPadding)
 199                                 sf.FormatFlags |= StringFormatFlags.FitBlackBox;
 200
 201                         // Text Wrapping
 202                         if ((flags & TextFormatFlags.SingleLine) == TextFormatFlags.SingleLine)
 203                                 sf.FormatFlags |= StringFormatFlags.NoWrap;
 204                         else if ((flags & TextFormatFlags.TextBoxControl) == TextFormatFlags.TextBoxControl)
 205                                 sf.FormatFlags |= StringFormatFlags.LineLimit;
 206
 207                         // Other Flags
 208                         if ((flags & TextFormatFlags.RightToLeft) == TextFormatFlags.RightToLeft)
 209                                 sf.FormatFlags |= StringFormatFlags.DirectionRightToLeft;
 210                         if ((flags & TextFormatFlags.NoClipping) == TextFormatFlags.NoClipping)
 211                                 sf.FormatFlags |= StringFormatFlags.NoClip;
 212                         sf.FormatFlags |= StringFormatFlags.NoClip;
 213
 214                         return sf;
 215                 }
 216                 #endregion
 217
 218                 #region DllImports (Windows)
 219                 [DllImport ("user32", CharSet = CharSet.Unicode)]
 220                 static extern int DrawText (IntPtr hdc, string lpStr, int nCount, ref VisualStyles.UXTheme.RECT lpRect, int wFormat);
 221
 222                 [DllImport ("gdi32")]
 223                 static extern int SetTextColor (IntPtr hdc, int crColor);
 224
 225                 [DllImport ("gdi32")]
 226                 private extern static IntPtr SelectObject (IntPtr hDC, IntPtr hObject);
 227
 228                 [DllImport ("gdi32")]
 229                 static extern int SetBkColor (IntPtr hdc, int crColor);
 230
 231                 [DllImport ("gdi32")]
 232                 static extern int SetBkMode (IntPtr hdc, int iBkMode);
 233
 234                 [DllImport ("gdi32")]
 235                 static extern bool GetTextExtentExPoint (IntPtr hdc, string lpszStr, int cchString, int nMaxExtent, IntPtr lpnFit, IntPtr alpDx, out VisualStyles.UXTheme.SIZE lpSize);
 236
 237                 [DllImport ("gdi32")]
 238                 static extern bool GetTextExtentPoint32 (IntPtr hdc, string lpString, int cbString, out VisualStyles.UXTheme.SIZE lpSize);
 239                 #endregion
 240         }
 241
 242 }
 243 #endif