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                 #region Public Methods
  40                 [MonoTODO("This should be correct for Windows, other platforms need a more accurate fallback method than the one provided")]
  41                 public static void DrawText (IDeviceContext dc, string text, Font font, Rectangle bounds, Color foreColor, TextFormatFlags flags)
  42                 {
  43                         if (Environment.OSVersion.Platform == PlatformID.Win32NT || Environment.OSVersion.Platform == PlatformID.Win32Windows) {
  44                                 Rectangle new_bounds = bounds;
  45                                 new_bounds.Offset ((int)(dc as Graphics).Transform.OffsetX + 0, (int)(dc as Graphics).Transform.OffsetY + 0);
  46                                 IntPtr hdc = dc.GetHdc ();
  47
  48                                 SetTextColor (hdc, ColorTranslator.ToWin32 (foreColor));
  49                                 SetBkMode (hdc, 1);     //1-Transparent, 2-Opaque
  50
  51                                 VisualStyles.UXTheme.RECT r = VisualStyles.UXTheme.RECT.FromRectangle (new_bounds);
  52
  53                                 if (font != null)
  54                                         SelectObject (hdc, font.ToHfont ());
  55
  56                                 DrawText (hdc, text, text.Length, ref r, (int)flags);
  57                                 dc.ReleaseHdc ();
  58                         }
  59                         else {
  60                                 Graphics g;
  61
  62                                 if (dc is Graphics)
  63                                         g = (Graphics)dc;
  64                                 else
  65                                         g = Graphics.FromHdc (dc.GetHdc ());
  66
  67                                 StringFormat sf = FlagsToStringFormat (flags);
  68
  69                                 using (Brush b = new SolidBrush (foreColor))
  70                                         g.DrawString (text, font, b, bounds, sf);
  71
  72                                 if (!(dc is Graphics)) {
  73                                         g.Dispose ();
  74                                         dc.ReleaseHdc ();
  75                                 }
  76                         }
  77                 }
  78
  79                 [MonoTODO ("This should be correct for Windows, other platforms need a more accurate fallback method than the one provided")]
  80                 public static void DrawText (IDeviceContext dc, string text, Font font, Point pt, Color foreColor, TextFormatFlags flags)
  81                 {
  82                         if (Environment.OSVersion.Platform == PlatformID.Win32NT || Environment.OSVersion.Platform == PlatformID.Win32Windows) {
  83                                 IntPtr hdc = dc.GetHdc ();
  84
  85                                 SetTextColor (hdc, ColorTranslator.ToWin32 (foreColor));
  86                                 SetBkMode (hdc, 1);     //1-Transparent, 2-Opaque
  87
  88                                 Size sz = MeasureText(text, font);
  89
  90                                 VisualStyles.UXTheme.RECT r = new System.Windows.Forms.VisualStyles.UXTheme.RECT(pt.X, pt.Y, pt.X + sz.Width, pt.Y + sz.Height);
  91
  92                                 if (font != null)
  93                                         SelectObject (hdc, font.ToHfont ());
  94
  95                                 DrawText (hdc, text, text.Length, ref r, (int)flags);
  96                                 dc.ReleaseHdc ();
  97                         }
  98                         else {
  99                                 Graphics g;
 100
 101                                 if (dc is Graphics)
 102                                         g = (Graphics)dc;
 103                                 else
 104                                         g = Graphics.FromHdc (dc.GetHdc ());
 105
 106                                 StringFormat sf = FlagsToStringFormat (flags);
 107
 108                                 using (Brush b = new SolidBrush (foreColor))
 109                                         g.DrawString (text, font, b, pt, sf);
 110
 111                                 if (!(dc is Graphics)) {
 112                                         g.Dispose ();
 113                                         dc.ReleaseHdc ();
 114                                 }
 115                         }
 116                 }
 117
 118                 [MonoTODO ("This should be correct for Windows, other platforms need a more accurate fallback method than the one provided")]
 119                 public static Size MeasureText (string text, Font font)
 120                 {
 121                         if (Environment.OSVersion.Platform == PlatformID.Win32NT || Environment.OSVersion.Platform == PlatformID.Win32Windows) {
 122                                 Bitmap b = new Bitmap (5, 5);
 123                                 Graphics g = Graphics.FromImage (b);
 124
 125                                 IntPtr hdc = g.GetHdc ();
 126
 127                                 if (font != null)
 128                                         SelectObject (hdc, font.ToHfont ());
 129
 130                                 VisualStyles.UXTheme.SIZE text_size = new System.Windows.Forms.VisualStyles.UXTheme.SIZE();
 131
 132                                 GetTextExtentPoint32 (hdc, text, text.Length, out text_size);
 133
 134                                 g.ReleaseHdc();
 135
 136                                 Size retval = text_size.ToSize();
 137                                 //retval.Height += 4;
 138                                 if (retval.Width > 0) retval.Width += 6;
 139                                 return retval;
 140                         }
 141                         else {
 142                                 Bitmap b = new Bitmap (5, 5);
 143                                 Graphics g = Graphics.FromImage (b);
 144
 145                                 Size retval = g.MeasureString(text,font).ToSize();
 146                                 if (retval.Width > 0) retval.Width += 6;
 147                                 return retval;
 148                         }
 149                 }
 150                 #endregion
 151
 152                 #region Private Methods
 153                 private static StringFormat FlagsToStringFormat (TextFormatFlags flags)
 154                 {
 155                         StringFormat sf = new StringFormat ();
 156
 157                         // Translation table: http://msdn.microsoft.com/msdnmag/issues/06/03/TextRendering/default.aspx?fig=true#fig4
 158
 159                         // Horizontal Alignment
 160                         if ((flags & TextFormatFlags.HorizontalCenter) == TextFormatFlags.HorizontalCenter)
 161                                 sf.Alignment = StringAlignment.Center;
 162                         else if ((flags & TextFormatFlags.Right) == TextFormatFlags.Right)
 163                                 sf.Alignment = StringAlignment.Far;
 164                         else
 165                                 sf.Alignment = StringAlignment.Near;
 166
 167                         // Vertical Alignment
 168                         if ((flags & TextFormatFlags.Bottom) == TextFormatFlags.Bottom)
 169                                 sf.LineAlignment = StringAlignment.Far;
 170                         else if ((flags & TextFormatFlags.VerticalCenter) == TextFormatFlags.VerticalCenter)
 171                                 sf.LineAlignment = StringAlignment.Center;
 172                         else
 173                                 sf.LineAlignment = StringAlignment.Near;
 174
 175                         // Ellipsis
 176                         if ((flags & TextFormatFlags.EndEllipsis) == TextFormatFlags.EndEllipsis)
 177                                 sf.Trimming = StringTrimming.EllipsisCharacter;
 178                         else if ((flags & TextFormatFlags.PathEllipsis) == TextFormatFlags.PathEllipsis)
 179                                 sf.Trimming = StringTrimming.EllipsisPath;
 180                         else if ((flags & TextFormatFlags.WordEllipsis) == TextFormatFlags.WordEllipsis)
 181                                 sf.Trimming = StringTrimming.EllipsisWord;
 182                         else
 183                                 sf.Trimming = StringTrimming.Character;
 184
 185                         // Hotkey Prefix
 186                         if ((flags & TextFormatFlags.NoPrefix) == TextFormatFlags.NoPrefix)
 187                                 sf.HotkeyPrefix = HotkeyPrefix.None;
 188                         else if ((flags & TextFormatFlags.HidePrefix) == TextFormatFlags.HidePrefix)
 189                                 sf.HotkeyPrefix = HotkeyPrefix.Hide;
 190                         else
 191                                 sf.HotkeyPrefix = HotkeyPrefix.Show;
 192
 193                         // Text Padding
 194                         if ((flags & TextFormatFlags.NoPadding) == TextFormatFlags.NoPadding)
 195                                 sf.FormatFlags |= StringFormatFlags.FitBlackBox;
 196
 197                         // Text Wrapping
 198                         if ((flags & TextFormatFlags.SingleLine) == TextFormatFlags.SingleLine)
 199                                 sf.FormatFlags |= StringFormatFlags.NoWrap;
 200                         else if ((flags & TextFormatFlags.TextBoxControl) == TextFormatFlags.TextBoxControl)
 201                                 sf.FormatFlags |= StringFormatFlags.LineLimit;
 202
 203                         // Other Flags
 204                         if ((flags & TextFormatFlags.RightToLeft) == TextFormatFlags.RightToLeft)
 205                                 sf.FormatFlags |= StringFormatFlags.DirectionRightToLeft;
 206                         if ((flags & TextFormatFlags.NoClipping) == TextFormatFlags.NoClipping)
 207                                 sf.FormatFlags |= StringFormatFlags.NoClip;
 208                         sf.FormatFlags |= StringFormatFlags.NoClip;
 209
 210                         return sf;
 211                 }
 212                 #endregion
 213
 214                 #region DllImports (Windows)
 215                 [DllImport ("user32", CharSet = CharSet.Unicode)]
 216                 static extern int DrawText (IntPtr hdc, string lpStr, int nCount, ref VisualStyles.UXTheme.RECT lpRect, int wFormat);
 217
 218                 [DllImport ("gdi32")]
 219                 static extern int SetTextColor (IntPtr hdc, int crColor);
 220
 221                 [DllImport ("gdi32")]
 222                 private extern static IntPtr SelectObject (IntPtr hDC, IntPtr hObject);
 223
 224                 [DllImport ("gdi32")]
 225                 static extern int SetBkColor (IntPtr hdc, int crColor);
 226
 227                 [DllImport ("gdi32")]
 228                 static extern int SetBkMode (IntPtr hdc, int iBkMode);
 229
 230                 [DllImport ("gdi32")]
 231                 static extern bool GetTextExtentExPoint (IntPtr hdc, string lpszStr, int cchString, int nMaxExtent, IntPtr lpnFit, IntPtr alpDx, out VisualStyles.UXTheme.SIZE lpSize);
 232
 233                 [DllImport ("gdi32")]
 234                 static extern bool GetTextExtentPoint32 (IntPtr hdc, string lpString, int cbString, out VisualStyles.UXTheme.SIZE lpSize);
 235                 #endregion
 236         }
 237
 238 }
 239 #endif