title: Some Unicode characters are not drawn using DrawString method
body: <p>This is one of the strange behavior of csharp code under my testing. </p>
  
  <p>I use DrawString method to draw some unicode character under Times New Roman Font. However, I can draw some characters and but some characters are just drawn as blank square (i.e. unsupported character. </p>
  
  <p>To elaborate more, I can draw  42 (*) and 43 (+) without any problem using DrawString method.</p>
  
  <p>But I can not draw 9978 and 9900. Both 9978 and 9900 are the supported characters by Times New Roman. Check the font map here. </p>
  
  <p><a href="https://www.martinstoeckli.ch/fontmap/fontmap.html" rel="nofollow noreferrer">https://www.martinstoeckli.ch/fontmap/fontmap.html</a></p>
  
  <p>For your information, when I try to print the same characters in the text box window control, everything works fine. Textbox show all the supported characters including 9978 and 9900.</p>
  
  <p>However, just this DrawString method is inconsistent under my testing. Why I can not draw these supported characters under the font using DrawString method ? </p>
  
  <pre><code>int unicodeIndex = 10728;
  
  this._provider = new CultureInfo("en-us");
  
  string unicodeString = ((char)unicodeIndex).ToString(_provider);
  
  this.Font = new Font("Times New Roman", 10);
  
  
  int x = 200;
  int y = 200;
  
  SizeF sizef = g.MeasureString(unicodeString+"W", this.Font, new PointF(x, y), _sformat);
  int w = Convert.ToInt32(sizef.Width) + 2;
  int h = Convert.ToInt32(sizef.Height) + 2;
  
  
  RectangleF rectf = new RectangleF(x, y-h/2, w, h);
  
  
  g.DrawString(unicodeString, this.Font, myBrush, rectf, myFormat);
  </code></pre>
  
  <p>Some more clue here as this seems tough problem. </p>
  
  <p>I am currently using East Asian Language pack installed on my Window.
  Is there any possibility that East Asian Language pack installed on my window can cause this problem ? For example, in localized window with Chinese and Japanese language, "Times New Roman" font might be not called correctly ? Just guess though.</p>