mcs/class/Microsoft.JScript/Microsoft.JScript/NumberPrototype.cs

   1 //
   2 // NumberPrototype.cs:
   3 //
   4 // Author:
   5 //      Cesar Lopez Nataren (cesar@ciencias.unam.mx)
   6 //
   7 // (C) 2003, Cesar Lopez Nataren
   8 //
   9
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System;
  32 using System.Text;
  33 using System.Globalization;
  34
  35 namespace Microsoft.JScript {
  36
  37         public class NumberPrototype : NumberObject {
  38
  39                 internal static NumberPrototype Proto = new NumberPrototype ();
  40
  41                 public static NumberConstructor constructor {
  42                         get { return NumberConstructor.Ctr; }
  43                 }
  44
  45                 [JSFunctionAttribute (JSFunctionAttributeEnum.HasThisObject, JSBuiltin.Number_toExponential)]
  46                 public static string toExponential (object thisObj, object fractionDigits)
  47                 {
  48                         throw new NotImplementedException ();
  49                 }
  50
  51                 [JSFunctionAttribute (JSFunctionAttributeEnum.HasThisObject, JSBuiltin.Number_toFixed)]
  52                 public static string toFixed (object thisObj, double fractionDigits)
  53                 {
  54                         if (!Convert.IsNumber (thisObj))
  55                                 throw new JScriptException (JSError.NumberExpected);
  56
  57                         double value = Convert.ToNumber (thisObj);
  58                         int prec = Convert.ToInt32 (fractionDigits);
  59
  60                         if (prec < 0 || prec > 21)
  61                                 throw new JScriptException (JSError.PrecisionOutOfRange);
  62
  63                         return value.ToString ("F" + prec, CultureInfo.InvariantCulture);
  64                 }
  65
  66                 [JSFunctionAttribute (JSFunctionAttributeEnum.HasThisObject, JSBuiltin.Number_toLocaleString)]
  67                 public static string toLocaleString (object thisObj)
  68                 {
  69                         if (!Convert.IsNumber (thisObj))
  70                                 throw new JScriptException (JSError.NumberExpected);
  71                         else
  72                                 return Convert.ToNumber (thisObj).ToString ("N");
  73                 }
  74
  75                 [JSFunctionAttribute (JSFunctionAttributeEnum.HasThisObject, JSBuiltin.Number_toPrecision)]
  76                 public static string toPrecision (object thisObj, object precision)
  77                 {
  78                         throw new NotImplementedException ();
  79                 }
  80
  81                 internal static char [] Digits = new char [] {
  82                         '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
  83                         'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
  84                         'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't',
  85                         'u', 'v', 'w', 'x', 'y', 'z'
  86                 };
  87
  88
  89                 //
  90                 // We aren't 100% compatible to MS JS.NET here, because we sometimes produce slightly more
  91                 // of the fractional digits. This shouldn't cause any trouble.
  92                 //
  93                 [JSFunctionAttribute (JSFunctionAttributeEnum.HasThisObject, JSBuiltin.Number_toString)]
  94                 public static string toString (object thisObj, object radix)
  95                 {
  96                         if (!Convert.IsNumber (thisObj))
  97                                 throw new JScriptException (JSError.NumberExpected);
  98
  99                         double value = Convert.ToNumber (thisObj);
 100
 101                         if (Double.IsNaN (value))
 102                                 return "NaN";
 103                         else if (Double.IsPositiveInfinity (value))
 104                                 return "Infinity";
 105                         else if (Double.IsNegativeInfinity (value))
 106                                 return "-Infinity";
 107
 108                         int _radix = 10;
 109                         if (radix != null) {
 110                                 _radix = Convert.ToInt32 (radix);
 111                                 if (_radix < 2)
 112                                         _radix = 10;
 113                                 else if (_radix > Digits.Length)
 114                                         _radix = 10;
 115                         }
 116                         if (_radix == 10)
 117                                 return value.ToString (CultureInfo.InvariantCulture);
 118
 119                         string result = "";
 120                         bool negative = false;
 121                         if (value < 0) {
 122                                 negative = true;
 123                                 value = Math.Abs (value);
 124                         }
 125
 126                         long whole = (long) value;
 127                         double frac = value - whole;
 128                         long digit;
 129
 130                         while (whole >= 1) {
 131                                 whole = Math.DivRem (whole, _radix, out digit);
 132                                 result = Digits [digit] + result;
 133                         }
 134
 135                         if (result.Length == 0)
 136                                 result = "0";
 137
 138                         int frac_digits = _radix;
 139                         string frac_buf = "";
 140                         bool has_frac = false;
 141
 142                         while (frac != 0 && frac_digits < 50) {
 143                                 frac *= _radix;
 144                                 digit = (long) frac;
 145                                 frac -= digit;
 146
 147                                 if (digit == 0)
 148                                         frac_buf += "0";
 149                                 else {
 150                                         if (!has_frac) result += ".";
 151                                         result += frac_buf + Digits [digit];
 152                                         frac_buf = "";
 153                                         has_frac = true;
 154                                 }
 155
 156                                 frac_digits++;
 157                         }
 158
 159                         if (negative)
 160                                 return "-" + result;
 161                         else
 162                                 return result;
 163                 }
 164
 165                 [JSFunctionAttribute (JSFunctionAttributeEnum.HasThisObject, JSBuiltin.Number_valueOf)]
 166                 public static object valueOf (object thisObj)
 167                 {
 168                         if (!Convert.IsNumber (thisObj))
 169                                 throw new JScriptException (JSError.NumberExpected);
 170                         else
 171                                 return Convert.ToNumber (thisObj);
 172                 }
 173         }
 174 }