mcs/class/System.Data/System.Data/DataRelation.cs

   1 //
   2 // System.Data.DataRelation.cs
   3 //
   4 // Author:
   5 //   Daniel Morgan <danmorg@sc.rr.com>
   6 //   Alan Tam Siu Lung <Tam@SiuLung.com>
   7 //   Tim Coleman <tim@timcoleman.com>
   8 //
   9 // (C) 2002 Daniel Morgan
  10 // (C) 2002 Ximian, Inc.
  11 // Copyright (C) Tim Coleman, 2003
  12 //
  13
  14 using System;
  15 using System.ComponentModel;
  16 using System.Runtime.Serialization;
  17
  18 namespace System.Data
  19 {
  20         /// <summary>
  21         /// DataRelation is used for a parent/child relationship
  22         /// between two DataTable objects
  23         /// </summary>
  24         [Editor]
  25         [DefaultProperty ("RelationName")]
  26         [Serializable]
  27         public class DataRelation {
  28                 private DataSet dataSet;
  29                 private string relationName;
  30                 private UniqueConstraint parentKeyConstraint;
  31                 private ForeignKeyConstraint childKeyConstraint;
  32                 private DataColumn[] parentColumns;
  33                 private DataColumn[] childColumns;
  34                 private bool nested;
  35                 internal bool createConstraints;
  36                 private PropertyCollection extendedProperties;
  37                 private PropertyChangedEventHandler onPropertyChangingDelegate;
  38
  39                 #region Constructors
  40
  41                 public DataRelation (string relationName, DataColumn parentColumn, DataColumn childColumn)
  42                 : this(relationName, parentColumn, childColumn, true)
  43                 {
  44                 }
  45
  46                 public DataRelation (string relationName, DataColumn[] parentColumns, DataColumn[] childColumns)
  47                 : this(relationName, parentColumns, childColumns, true)
  48                 {
  49                 }
  50
  51                 public DataRelation (string relationName, DataColumn parentColumn, DataColumn childColumn, bool createConstraints)
  52                 : this(relationName, new DataColumn[] { parentColumn }, new DataColumn[] { childColumn }, createConstraints)
  53                 {
  54                 }
  55
  56                 public DataRelation (string relationName, DataColumn[] parentColumns, DataColumn[] childColumns, bool createConstraints)
  57                 {
  58                         this.extendedProperties = new PropertyCollection();
  59                         if (relationName == null) relationName = string.Empty;
  60                         this.relationName = relationName;
  61                         if (parentColumns == null) throw new ArgumentNullException ();
  62                         this.parentColumns = parentColumns;
  63                         if (childColumns == null) throw new ArgumentNullException ();
  64                         this.childColumns = childColumns;
  65                         this.createConstraints = createConstraints;
  66                         if (parentColumns.Length != childColumns.Length)
  67                                 throw new ArgumentException ("ParentColumns and ChildColumns should be the same length");
  68                         DataTable parentTable = parentColumns[0].Table;
  69                         DataTable childTable = childColumns[0].Table;
  70                         if (parentTable.DataSet != childTable.DataSet)
  71                                 throw new InvalidConstraintException ();
  72                         foreach (DataColumn column in parentColumns)
  73                                 if (column.Table != parentTable)
  74                                         throw new InvalidConstraintException ();
  75                         foreach (DataColumn column in childColumns)
  76                                 if (column.Table != childTable)
  77                                         throw new InvalidConstraintException ();
  78                 }
  79
  80                 [MonoTODO]
  81                 [Browsable (false)]
  82                 public DataRelation (string relationName, string parentTableName, string childTableName, string[] parentColumnNames, string[] childColumnNames, bool nested)
  83                 {
  84                         throw new NotImplementedException ();
  85                 }
  86
  87 #if NET_1_2
  88                 [MonoTODO]
  89                 public DataRelation (string relationName, string parentTableName, string parentTableNamespace, string childTableName, string childTableNamespace, string[] parentColumnNames, string[] childColumnNames, bool nested)
  90                 {
  91                         throw new NotImplementedException ();
  92                 }
  93 #endif
  94
  95                 #endregion // Constructors
  96
  97                 #region Properties
  98
  99                 [DataCategory ("Data")]
 100                 [DataSysDescription ("Indicates the child columns of this relation.")]
 101                 public virtual DataColumn[] ChildColumns {
 102                         get {
 103                                 return childColumns;
 104                         }
 105                 }
 106
 107                 public virtual ForeignKeyConstraint ChildKeyConstraint {
 108                         get {
 109                                 return childKeyConstraint;
 110                         }
 111                 }
 112
 113                 internal void SetChildKeyConstraint(ForeignKeyConstraint foreignKeyConstraint) {
 114                         childKeyConstraint = foreignKeyConstraint;
 115                 }
 116
 117                 public virtual DataTable ChildTable {
 118                         get {
 119                                 return childColumns[0].Table;
 120                         }
 121                 }
 122
 123                 [Browsable (false)]
 124                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 125                 public virtual DataSet DataSet {
 126                         get {
 127                                 return childColumns[0].Table.DataSet;
 128                         }
 129                 }
 130
 131                 [Browsable (false)]
 132                 [DataCategory ("Data")]
 133                 [DataSysDescription ("The collection that holds custom user information.")]
 134                 public PropertyCollection ExtendedProperties {
 135                         get {
 136                                 if (extendedProperties == null)
 137                                         extendedProperties = new PropertyCollection();
 138                                 return extendedProperties;
 139                         }
 140                 }
 141
 142                 [DataCategory ("Data")]
 143                 [DataSysDescription ("Indicates whether relations are nested.")]
 144                 [DefaultValue (false)]
 145                 public virtual bool Nested {
 146                         get {
 147                                 return nested;
 148                         }
 149
 150                         set {
 151                                 nested = value;
 152                         }
 153                 }
 154
 155                 [DataCategory ("Data")]
 156                 [DataSysDescription ("Indicates the parent columns of this relation.")]
 157                 public virtual DataColumn[] ParentColumns {
 158                         get {
 159                                 return parentColumns;
 160                         }
 161                 }
 162
 163                 public virtual UniqueConstraint ParentKeyConstraint {
 164                         get {
 165                                 return parentKeyConstraint;
 166                         }
 167                 }
 168
 169                 internal void SetParentKeyConstraint(UniqueConstraint uniqueConstraint) {
 170                         parentKeyConstraint = uniqueConstraint;
 171                 }
 172
 173                 internal void SetDataSet(DataSet ds) {
 174                         dataSet = ds;
 175                 }
 176
 177                 public virtual DataTable ParentTable {
 178                         get {
 179                                 return parentColumns[0].Table;
 180                         }
 181                 }
 182
 183                 [DataCategory ("Data")]
 184                 [DataSysDescription ("The name used to look up this relation in the Relations collection of a DataSet.")]
 185                 [DefaultValue ("")]
 186                 public virtual string RelationName {
 187                         get {
 188                                 return relationName;
 189                         }
 190
 191                         set {
 192                                 relationName = value;
 193                         }
 194                 }
 195
 196                 #endregion // Properties
 197
 198                 #region Methods
 199
 200                 protected void CheckStateForProperty ()
 201                 {
 202                         // TODO: check consistency of constraints
 203                         DataTable parentTable = parentColumns[0].Table;
 204                         DataTable childTable = parentColumns[0].Table;
 205                         if (parentTable.DataSet != childTable.DataSet)
 206                                 throw new DataException ();
 207                         bool allColumnsEqual = false;
 208                         for (int colCnt = 0; colCnt < parentColumns.Length; ++colCnt) {
 209                                 if (!parentColumns [colCnt].DataType.Equals (childColumns [colCnt].DataType))
 210                                         throw new DataException ();
 211                                 if (parentColumns [colCnt] != childColumns [colCnt]) allColumnsEqual = false;
 212                         }
 213                         if (allColumnsEqual) throw new DataException ();
 214                 }
 215
 216                 protected internal void OnPropertyChanging (PropertyChangedEventArgs pcevent)
 217                 {
 218                         if (onPropertyChangingDelegate != null)
 219                                 onPropertyChangingDelegate (this, pcevent);
 220                 }
 221
 222                 protected internal void RaisePropertyChanging (string name)
 223                 {
 224                         OnPropertyChanging(new PropertyChangedEventArgs(name));
 225                 }
 226
 227                 public override string ToString ()
 228                 {
 229                         return relationName;
 230                 }
 231
 232                 #endregion // Methods
 233         }
 234 }