mcs/class/System.Data/System.Data/Constraint.cs

   1 //
   2 // System.Data.Constraint.cs
   3 //
   4 // Author:
   5 //      Franklin Wise <gracenote@earthlink.net>
   6 //      Daniel Morgan
   7 //      Tim Coleman (tim@timcoleman.com)
   8 //
   9 //
  10 // (C) Ximian, Inc. 2002
  11 // Copyright (C) Tim Coleman, 2002
  12 //
  13
  14 using System;
  15 using System.Collections;
  16 using System.ComponentModel;
  17 using System.Runtime.InteropServices;
  18 using System.Runtime.Serialization;
  19
  20 namespace System.Data {
  21         [Serializable]
  22         internal delegate void DelegateConstraintNameChange (object sender, string newName);
  23
  24         [DefaultProperty ("ConstraintName")]
  25         [Serializable]
  26         public abstract class Constraint
  27         {
  28                 internal event DelegateConstraintNameChange BeforeConstraintNameChange;
  29
  30                 //if constraintName is not set then a name is
  31                 //created when it is added to
  32                 //the ConstraintCollection
  33                 //it can not be set to null, empty or duplicate
  34                 //once it has been added to the collection
  35                 private string _constraintName = null;
  36                 private PropertyCollection _properties = null;
  37
  38                 //Used for membership checking
  39                 private ConstraintCollection _constraintCollection;
  40
  41                 DataSet dataSet;
  42
  43                 protected Constraint ()
  44                 {
  45                         dataSet = null;
  46                         _properties = new PropertyCollection();
  47                 }
  48
  49                 protected internal virtual DataSet _DataSet {
  50                         get { return dataSet; }
  51                 }
  52
  53                 [DataCategory ("Data")]
  54                 [DataSysDescription ("Indicates the name of this constraint.")]
  55                 [DefaultValue ("")]
  56                 public virtual string ConstraintName {
  57                         get{ return "" + _constraintName; }
  58                         set{
  59                                 //This should only throw an exception when it
  60                                 //is a member of a ConstraintCollection which
  61                                 //means we should let the ConstraintCollection
  62                                 //handle exceptions when this value changes
  63                                 _onConstraintNameChange(value);
  64                                 _constraintName = value;
  65                         }
  66                 }
  67
  68                 [Browsable (false)]
  69                 [DataCategory ("Data")]
  70                 [DataSysDescription ("The collection that holds custom user information.")]
  71                 public PropertyCollection ExtendedProperties {
  72                         get { return _properties; }
  73                 }
  74
  75                 [DataSysDescription ("Indicates the table of this constraint.")]
  76                 public abstract DataTable Table {
  77                         get;
  78                 }
  79
  80                 internal ConstraintCollection ConstraintCollection {
  81                         get{ return _constraintCollection; }
  82                         set{ _constraintCollection = value; }
  83                 }
  84
  85                 private void _onConstraintNameChange (string newName)
  86                 {
  87                         if (null != BeforeConstraintNameChange)
  88                         {
  89                                 BeforeConstraintNameChange (this, newName);
  90                         }
  91                 }
  92
  93                 //call once before adding a constraint to a collection
  94                 //will throw an exception to prevent the add if a rule is broken
  95                 internal virtual void AddToConstraintCollectionSetup (ConstraintCollection collection)
  96                 {
  97                 }
  98
  99                 internal virtual void AssertConstraint ()
 100                 {
 101                 }
 102
 103                 internal virtual void AssertConstraint (DataRow row)
 104                 {
 105                 }
 106
 107                 //call once before removing a constraint to a collection
 108                 //can throw an exception to prevent the removal
 109                 internal virtual void RemoveFromConstraintCollectionCleanup (ConstraintCollection collection)
 110                 {
 111                 }
 112
 113                 [MonoTODO]
 114                 protected void CheckStateForProperty ()
 115                 {
 116                         throw new NotImplementedException ();
 117                 }
 118
 119                 protected internal void SetDataSet (DataSet dataSet)
 120                 {
 121                         this.dataSet = dataSet;
 122                 }
 123
 124                 /// <summary>
 125                 /// Gets the ConstraintName, if there is one, as a string.
 126                 /// </summary>
 127                 public override string ToString ()
 128                 {
 129                         return "" + _constraintName;
 130                 }
 131
 132         }
 133 }