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  Confused Dav...

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  Switch question

  Sep 13, 2014 05:26 PM|Confused Dave|LINK

  How would you write this in C#?

  Select Case Asc(tChr)
  Case 65 To 90, 97 To 122, 48 To 57
  End Select

  
  Thanks

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  Rion William...

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  Re: Switch question

  Sep 13, 2014 05:44 PM|Rion Williams|LINK

  C# doesn't support ranges for switch statements like Visual Basic does.

  The easiest approach might be to use an explicit if-statement that checks to see if it falls into your specific range. Additionally, the Asc() function returns an integer that corresponds to a certain character, which you could use by just converting the character to an integer as seen below :

  // Get your integer value
  var x = Convert.ToInt32(tChr);
  
  // Determine if it falls into your range
  if(x >= 65 && x <= 90)
  {
       // Case 1: 65 - 90
  }
  else if(x >= 97 && x <= 122)
  {
       // Case 2: 97 - 122
  }
  else if(x >= 48 && x <= 57)
  {
       // Case 3: 48 - 57
  }

  or if you needed to trigger an event for any of these, just use :

  // Get your integer value
  var x = Convert.ToInt32(tChr);
  
  // Determine if it falls into a range
  if((x >= 65 && x <= 90) || (x >= 97 && x <= 122) || (x >= 48 && x <= 57))
  {
       // It falls into one of these ranges
  }

  Finally, if you wanted a more exact conversion, it would simply require you to list out all of the ranges similar to below :

  switch(Convert.ToInt32(tChr))
  {
        case 48:
        // Enumerate until 56 here
        case 57:
               // Cases 48 - 57
        break;
        case 65:
        // Enumerate until 89 here
        case 90:
               // Cases 65 - 90
        break;
        case 97:
        // Enumerate until 111 here
        case 112:
               // Cases 97 - 112
        break;
  }

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  gerrylowry

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  Re: Switch question

  Sep 15, 2014 03:08 PM|gerrylowry|LINK

  @Confused Dav...  TIMTOWTDI =. there is more than one way to do it

  Dave, you're simply trying to determine whether your value is a uppercase or lowercase letter, or a digit.

  Better is to allow the MSDN Framework to do that for you.

  "Char.IsLetterOrDigit Method (Char)" http://msdn.microsoft.com/en-us/library/cay4xx2f%28v=vs.110%29.aspx

  Here's a simpler solution based on Char.IsLetterOrDigit:

  Char space = ' '; // Decimal  32
  Char star  = '*'; // Decimal  42
  Char slash = '/'; // Decimal  47
  Char zero  = '0'; // Decimal  48
  Char nine  = '9'; // Decimal  57
  Char colon = ':'; // Decimal  58
  Char at    = '@'; // Decimal  64
  Char A     = 'A'; // Decimal  65
  Char Z     = 'Z'; // Decimal  90
  Char Lbrak = '['; // Decimal  91
  Char btick = '`'; // Decimal  96 
  Char a     = 'a'; // Decimal  97
  Char z     = 'z'; // Decimal 122
  Char curly = '{'; // Decimal 123

  Console.WriteLine("[{0}] {1}", space, Char.IsLetterOrDigit(space));
  Console.WriteLine("[{0}] {1}", star, Char.IsLetterOrDigit(star));
  Console.WriteLine("[{0}] {1}", slash, Char.IsLetterOrDigit(slash));
  Console.WriteLine("[{0}] {1}", zero,  Char.IsLetterOrDigit(zero));
  Console.WriteLine("[{0}] {1}", nine,  Char.IsLetterOrDigit(nine));
  Console.WriteLine("[{0}] {1}", colon, Char.IsLetterOrDigit(colon));
  Console.WriteLine("[{0}] {1}", at,    Char.IsLetterOrDigit(at));
  Console.WriteLine("[{0}] {1}", A,     Char.IsLetterOrDigit(A));
  Console.WriteLine("[{0}] {1}", Z,     Char.IsLetterOrDigit(Z));
  Console.WriteLine("[{0}] {1}", Lbrak, Char.IsLetterOrDigit(Lbrak));
  Console.WriteLine("[{0}] {1}", btick, Char.IsLetterOrDigit(btick));
  Console.WriteLine("[{0}] {1}", a,     Char.IsLetterOrDigit(a));
  Console.WriteLine("[{0}] {1}", z,     Char.IsLetterOrDigit(z));
  Console.WriteLine("[{0}] {1}", curly, Char.IsLetterOrDigit(curly));

  output:
  
  

  [ ] False
  [*] False
  [/] False
  [0] True
  [9] True
  [:] False
  [@] False
  [A] True
  [Z] True
  [[] False
  [`] False
  [a] True
  [z] True
  [{] False

  But there's a catch ... the .NET Framework is a Unicode world:

  Char a2dot = 'ä'; // a with umlaut
  
  Console.WriteLine("[{0}] {1}", a2dot, Char.IsLetterOrDigit(a2dot));

  output:

  [ä] True

  if there is any possibility that your data may contain letters like ä, ç, é, ...   et cetera, then here's a fix to stay within your range:

  Console.WriteLine("[{0}] {1}", a2dot, Char.IsLetterOrDigit(a2dot) && ((Int32)a2dot<123));

  output:

  [ä] False

  B-)  Gerry Lowry, Chief Training Architect, Paradigm Mentors Learning never ends... +1 705-999-9195 wasaga beach, ontario canada TIMTOWTDI =.there is more than one way to do it