docs/fundamentals/runtime-libraries/snippets/System/Console/Overview/csharp/example3.cs - main - aprogrammer/dotnet-docs

docs/fundamentals/runtime-libraries/snippets/System/Console/Overview/csharp/example3.cs
184 строки8 KB
Genevieve Warren
Add remarks for core types (#38970)
05 янв 2024, 22:14
05 янв 2024, 22:1471d1377
// dump a range of Unicode characters as a 16x16 array
// <Snippet4>
using System;
using System.IO;
using System.Globalization;
using System.Text;

public static class DisplayChars
{
   private static void Main(string[] args)
   {
      uint rangeStart = 0;
      uint rangeEnd = 0;
      bool setOutputEncodingToUnicode = true;
      // Get the current encoding so we can restore it.
      Encoding originalOutputEncoding = Console.OutputEncoding;

   	try
   	{
         switch(args.Length)
         {
            case 2:
               rangeStart = uint.Parse(args[0], NumberStyles.HexNumber);
               rangeEnd = uint.Parse(args[1], NumberStyles.HexNumber);
               setOutputEncodingToUnicode = true;
               break;
            case 3:
               if (! uint.TryParse(args[0], NumberStyles.HexNumber, null, out rangeStart))
                  throw new ArgumentException(String.Format("{0} is not a valid hexadecimal number.", args[0]));

               if (!uint.TryParse(args[1], NumberStyles.HexNumber, null, out rangeEnd))
                  throw new ArgumentException(String.Format("{0} is not a valid hexadecimal number.", args[1]));

               bool.TryParse(args[2], out setOutputEncodingToUnicode);
               break;
            default:
               Console.WriteLine("Usage: {0} <{1}> <{2}> [{3}]",
                                 Environment.GetCommandLineArgs()[0],
                                 "startingCodePointInHex",
                                 "endingCodePointInHex",
                                 "<setOutputEncodingToUnicode?{true|false, default:false}>");
               return;
         }

         if (setOutputEncodingToUnicode) {
            // This won't work before .NET Framework 4.5.
            try {
               // Set encoding using endianness of this system.
               // We're interested in displaying individual Char objects, so
               // we don't want a Unicode BOM or exceptions to be thrown on
               // invalid Char values.
               Console.OutputEncoding = new UnicodeEncoding(! BitConverter.IsLittleEndian, false);
               Console.WriteLine("\nOutput encoding set to UTF-16");
            }
            catch (IOException) {
               Console.OutputEncoding = new UTF8Encoding();
               Console.WriteLine("Output encoding set to UTF-8");
            }
         }
         else {
            Console.WriteLine("The console encoding is {0} (code page {1})",
                              Console.OutputEncoding.EncodingName,
                              Console.OutputEncoding.CodePage);
         }
         DisplayRange(rangeStart, rangeEnd);
      }
      catch (ArgumentException ex) {
         Console.WriteLine(ex.Message);
      }
      finally {
         // Restore console environment.
         Console.OutputEncoding = originalOutputEncoding;
      }
   }

   public static void DisplayRange(uint start, uint end)
   {
      const uint upperRange = 0x10FFFF;
      const uint surrogateStart = 0xD800;
      const uint surrogateEnd = 0xDFFF;

      if (end <= start) {
         uint t = start;
         start = end;
         end = t;
      }

      // Check whether the start or end range is outside of last plane.
      if (start > upperRange)
         throw new ArgumentException(String.Format("0x{0:X5} is outside the upper range of Unicode code points (0x{1:X5})",
                                                   start, upperRange));
      if (end > upperRange)
         throw new ArgumentException(String.Format("0x{0:X5} is outside the upper range of Unicode code points (0x{0:X5})",
                                                   end, upperRange));

      // Since we're using 21-bit code points, we can't use U+D800 to U+DFFF.
      if ((start < surrogateStart & end > surrogateStart) || (start >= surrogateStart & start <= surrogateEnd ))
         throw new ArgumentException(String.Format("0x{0:X5}-0x{1:X5} includes the surrogate pair range 0x{2:X5}-0x{3:X5}",
                                                   start, end, surrogateStart, surrogateEnd));
      uint last = RoundUpToMultipleOf(0x10, end);
      uint first = RoundDownToMultipleOf(0x10, start);

      uint rows = (last - first) / 0x10;

      for (uint r = 0; r < rows; ++r) {
         // Display the row header.
         Console.Write("{0:x5} ", first + 0x10 * r);

         for (uint c = 0; c < 0x10; ++c) {
            uint cur = (first + 0x10 * r + c);
            if (cur  < start) {
               Console.Write($" {(char)(0x20)} ");
            }
            else if (end < cur) {
               Console.Write($" {(char)(0x20)} ");
            }
            else {
               // the cast to int is safe, since we know that val <= upperRange.
               String chars = Char.ConvertFromUtf32( (int) cur);
               // Display a space for code points that are not valid characters.
               if (CharUnicodeInfo.GetUnicodeCategory(chars[0]) ==
                                               UnicodeCategory.OtherNotAssigned)
                  Console.Write($" {(char)(0x20)} ");
               // Display a space for code points in the private use area.
               else if (CharUnicodeInfo.GetUnicodeCategory(chars[0]) ==
                                              UnicodeCategory.PrivateUse)
                 Console.Write($" {(char)(0x20)} ");
               // Is surrogate pair a valid character?
               // Note that the console will interpret the high and low surrogate
               // as separate (and unrecognizable) characters.
               else if (chars.Length > 1 && CharUnicodeInfo.GetUnicodeCategory(chars, 0) ==
                                            UnicodeCategory.OtherNotAssigned)
                  Console.Write($" {(char)(0x20)} ");
               else
                  Console.Write($" {chars} ");
            }

            switch (c) {
               case 3: case 11:
                  Console.Write("-");
                  break;
               case 7:
                  Console.Write("--");
                  break;
            }
         }

         Console.WriteLine();
         if (0 < r && r % 0x10 == 0)
            Console.WriteLine();
      }
   }

   private static uint RoundUpToMultipleOf(uint b, uint u)
   {
      return RoundDownToMultipleOf(b, u) + b;
   }

   private static uint RoundDownToMultipleOf(uint b, uint u)
   {
      return u - (u % b);
   }
}
// If the example is run with the command line
//       DisplayChars 0400 04FF true
// the example displays the Cyrillic character set as follows:
//       Output encoding set to UTF-16
//       00400  Ѐ  Ё  Ђ  Ѓ - Є  Ѕ  І  Ї -- Ј  Љ  Њ  Ћ - Ќ  Ѝ  Ў  Џ
//       00410  А  Б  В  Г - Д  Е  Ж  З -- И  Й  К  Л - М  Н  О  П
//       00420  Р  С  Т  У - Ф  Х  Ц  Ч -- Ш  Щ  Ъ  Ы - Ь  Э  Ю  Я
//       00430  а  б  в  г - д  е  ж  з -- и  й  к  л - м  н  о  п
//       00440  р  с  т  у - ф  х  ц  ч -- ш  щ  ъ  ы - ь  э  ю  я
//       00450  ѐ  ё  ђ  ѓ - є  ѕ  і  ї -- ј  љ  њ  ћ - ќ  ѝ  ў  џ
//       00460  Ѡ  ѡ  Ѣ  ѣ - Ѥ  ѥ  Ѧ  ѧ -- Ѩ  ѩ  Ѫ  ѫ - Ѭ  ѭ  Ѯ  ѯ
//       00470  Ѱ  ѱ  Ѳ  ѳ - Ѵ  ѵ  Ѷ  ѷ -- Ѹ  ѹ  Ѻ  ѻ - Ѽ  ѽ  Ѿ  ѿ
//       00480  Ҁ  ҁ  ҂  ҃ - ҄  ҅  ҆  ҇ -- ҈  ҉  Ҋ  ҋ - Ҍ  ҍ  Ҏ  ҏ
//       00490  Ґ  ґ  Ғ  ғ - Ҕ  ҕ  Җ  җ -- Ҙ  ҙ  Қ  қ - Ҝ  ҝ  Ҟ  ҟ
//       004a0  Ҡ  ҡ  Ң  ң - Ҥ  ҥ  Ҧ  ҧ -- Ҩ  ҩ  Ҫ  ҫ - Ҭ  ҭ  Ү  ү
//       004b0  Ұ  ұ  Ҳ  ҳ - Ҵ  ҵ  Ҷ  ҷ -- Ҹ  ҹ  Һ  һ - Ҽ  ҽ  Ҿ  ҿ
//       004c0  Ӏ  Ӂ  ӂ  Ӄ - ӄ  Ӆ  ӆ  Ӈ -- ӈ  Ӊ  ӊ  Ӌ - ӌ  Ӎ  ӎ  ӏ
//       004d0  Ӑ  ӑ  Ӓ  ӓ - Ӕ  ӕ  Ӗ  ӗ -- Ә  ә  Ӛ  ӛ - Ӝ  ӝ  Ӟ  ӟ
//       004e0  Ӡ  ӡ  Ӣ  ӣ - Ӥ  ӥ  Ӧ  ӧ -- Ө  ө  Ӫ  ӫ - Ӭ  ӭ  Ӯ  ӯ
//       004f0  Ӱ  ӱ  Ӳ  ӳ - Ӵ  ӵ  Ӷ  ӷ -- Ӹ  ӹ  Ӻ  ӻ - Ӽ  ӽ  Ӿ  ӿ
// </Snippet4>