mcs/class/System.Data/System.Data.SqlTypes/SqlGuid.cs

   1 //
   2 // System.Data.SqlTypes.SqlGuid
   3 //
   4 // Author:
   5 //   Tim Coleman <tim@timcoleman.com>
   6 //   Ville Palo <vi64pa@koti.soon.fi>
   7 //
   8 // (C) Copyright 2002 Tim Coleman
   9 //
  10
  11 //
  12 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33
  34 using System;
  35 using System.Globalization;
  36
  37 namespace System.Data.SqlTypes
  38 {
  39         public struct SqlGuid : INullable, IComparable
  40         {
  41                 #region Fields
  42
  43                 Guid value;
  44
  45                 private bool notNull;
  46
  47                 public static readonly SqlGuid Null;
  48
  49                 #endregion
  50
  51                 #region Constructors
  52
  53                 public SqlGuid (byte[] value)
  54                 {
  55                         this.value = new Guid (value);
  56                         notNull = true;
  57                 }
  58
  59                 public SqlGuid (Guid g)
  60                 {
  61                         this.value = g;
  62                         notNull = true;
  63                 }
  64
  65                 public SqlGuid (string s)
  66                 {
  67                         this.value = new Guid (s);
  68                         notNull = true;
  69                 }
  70
  71                 public SqlGuid (int a, short b, short c, byte d, byte e, byte f, byte g, byte h, byte i, byte j, byte k)
  72                 {
  73                         this.value = new Guid (a, b, c, d, e, f, g, h, i, j, k);
  74                         notNull = true;
  75                 }
  76
  77                 #endregion
  78
  79                 #region Properties
  80
  81                 public bool IsNull {
  82                         get { return !notNull; }
  83                 }
  84
  85                 public Guid Value {
  86                         get {
  87                                 if (this.IsNull)
  88                                         throw new SqlNullValueException ("The property contains Null.");
  89                                 else
  90                                         return value;
  91                         }
  92                 }
  93
  94                 private byte[] GetLastSixBytes()
  95                 {
  96                         byte [] lastSixBytes = new byte[6];
  97
  98                         byte[] guidArray = value.ToByteArray();
  99                         lastSixBytes[0] = guidArray[10];
 100                         lastSixBytes[1] = guidArray[11];
 101                         lastSixBytes[2] = guidArray[12];
 102                         lastSixBytes[3] = guidArray[13];
 103                         lastSixBytes[4] = guidArray[14];
 104                         lastSixBytes[5] = guidArray[15];
 105
 106                         return lastSixBytes;
 107                 }
 108
 109                 #endregion
 110
 111                 #region Methods
 112
 113                 public int CompareTo (object value)
 114                 {
 115                         if (value == null)
 116                                 return 1;
 117                         else if (!(value is SqlGuid))
 118                                 throw new ArgumentException (Locale.GetText ("Value is not a System.Data.SqlTypes.SqlGuid"));
 119                         else if (((SqlGuid)value).IsNull)
 120                                 return 1;
 121                         else
 122                                 // LAMESPEC : ms.net implementation actually compares all the 16 bytes.
 123                                 // This code is kept for future changes, if required.
 124                                 /*
 125                                 {
 126                                         //MSDN documentation says that CompareTo is different from
 127                                         //Guid's CompareTo. It uses the SQL Server behavior where
 128                                         //only the last 6 bytes of value are evaluated
 129                                         byte[] compareValue = ((SqlGuid)value).GetLastSixBytes();
 130                                         byte[] currentValue = GetLastSixBytes();
 131                                         for (int i = 0; i < 6; i++)
 132                                         {
 133                                                 if (currentValue[i] != compareValue[i]) {
 134                                                       return Compare(currentValue[i], compareValue[i]);
 135                                                 }
 136                                         }
 137                                         return 0;
 138                                 }
 139                                 */
 140                                 return this.value.CompareTo (((SqlGuid)value).Value);
 141
 142                 }
 143
 144
 145                 private static int Compare (uint x, uint y)
 146                 {
 147                         if (x < y) {
 148                                 return -1;
 149                         }
 150                         else {
 151                                 return 1;
 152                         }
 153                 }
 154
 155
 156                 public override bool Equals (object value)
 157                 {
 158                         if (!(value is SqlGuid))
 159                                 return false;
 160                         else if (this.IsNull && ((SqlGuid)value).IsNull)
 161                                 return true;
 162                         else if (((SqlGuid)value).IsNull)
 163                                 return false;
 164                         else
 165                                 return (bool) (this == (SqlGuid)value);
 166                 }
 167
 168                 public static SqlBoolean Equals (SqlGuid x, SqlGuid y)
 169                 {
 170                         return (x == y);
 171                 }
 172
 173                 public override int GetHashCode ()
 174                 {
 175                         byte [] bytes  = this.ToByteArray ();
 176
 177                         int result = 10;
 178                         foreach (byte b in  bytes) {
 179                                 result = 91 * result + b.GetHashCode ();
 180                         }
 181
 182                         return result;
 183                 }
 184
 185                 public static SqlBoolean GreaterThan (SqlGuid x, SqlGuid y)
 186                 {
 187                         return (x > y);
 188                 }
 189
 190                 public static SqlBoolean GreaterThanOrEqual (SqlGuid x, SqlGuid y)
 191                 {
 192                         return (x >= y);
 193                 }
 194
 195                 public static SqlBoolean LessThan (SqlGuid x, SqlGuid y)
 196                 {
 197                         return (x < y);
 198                 }
 199
 200                 public static SqlBoolean LessThanOrEqual (SqlGuid x, SqlGuid y)
 201                 {
 202                         return (x <= y);
 203                 }
 204
 205                 public static SqlBoolean NotEquals (SqlGuid x, SqlGuid y)
 206                 {
 207                         return (x != y);
 208                 }
 209
 210                 public static SqlGuid Parse (string s)
 211                 {
 212                         return new SqlGuid (s);
 213                 }
 214
 215                 public byte[] ToByteArray()
 216                 {
 217                         return value.ToByteArray ();
 218                 }
 219
 220                 public SqlBinary ToSqlBinary ()
 221                 {
 222                         return ((SqlBinary)this);
 223                 }
 224
 225                 public SqlString ToSqlString ()
 226                 {
 227                         return ((SqlString)this);
 228                 }
 229
 230                 public override string ToString ()
 231                 {
 232                         if (!notNull)
 233                                 return "Null";
 234                         else
 235                                 return value.ToString ();
 236                 }
 237
 238                 public static SqlBoolean operator == (SqlGuid x, SqlGuid y)
 239                 {
 240                         if (x.IsNull || y.IsNull) return SqlBoolean.Null;
 241                         return new SqlBoolean (x.Value == y.Value);
 242                 }
 243
 244                 public static SqlBoolean operator > (SqlGuid x, SqlGuid y)
 245                 {
 246                         if (x.IsNull || y.IsNull)
 247                                 return SqlBoolean.Null;
 248
 249                         if (x.Value.CompareTo (y.Value) > 0)
 250                                 return new SqlBoolean (true);
 251                         else
 252                                 return new SqlBoolean (false);
 253                 }
 254
 255                 public static SqlBoolean operator >= (SqlGuid x, SqlGuid y)
 256                 {
 257                         if (x.IsNull || y.IsNull)
 258                                 return SqlBoolean.Null;
 259
 260                         if (x.Value.CompareTo (y.Value) >= 0)
 261                                 return new SqlBoolean (true);
 262                         else
 263                                 return new SqlBoolean (false);
 264
 265                 }
 266
 267                 public static SqlBoolean operator != (SqlGuid x, SqlGuid y)
 268                 {
 269                         if (x.IsNull || y.IsNull) return SqlBoolean.Null;
 270                         return new SqlBoolean (!(x.Value == y.Value));
 271                 }
 272
 273                 public static SqlBoolean operator < (SqlGuid x, SqlGuid y)
 274                 {
 275                         if (x.IsNull || y.IsNull)
 276                                 return SqlBoolean.Null;
 277
 278                         if (x.Value.CompareTo (y.Value) < 0)
 279                                 return new SqlBoolean (true);
 280                         else
 281                                 return new SqlBoolean (false);
 282
 283                 }
 284
 285                 public static SqlBoolean operator <= (SqlGuid x, SqlGuid y)
 286                 {
 287                         if (x.IsNull || y.IsNull)
 288                                 return SqlBoolean.Null;
 289
 290                         if (x.Value.CompareTo (y.Value) <= 0)
 291                                 return new SqlBoolean (true);
 292                         else
 293                                 return new SqlBoolean (false);
 294                 }
 295
 296                 public static explicit operator SqlGuid (SqlBinary x)
 297                 {
 298                         return new SqlGuid (x.Value);
 299                 }
 300
 301                 public static explicit operator Guid (SqlGuid x)
 302                 {
 303                         return x.Value;
 304                 }
 305
 306                 public static explicit operator SqlGuid (SqlString x)
 307                 {
 308                         return new SqlGuid (x.Value);
 309                 }
 310
 311                 public static implicit operator SqlGuid (Guid x)
 312                 {
 313                         return new SqlGuid (x);
 314                 }
 315
 316                 #endregion
 317         }
 318 }
 319