mcs/class/System.Web/System.Web.UI.WebControls/Parameter.cs

   1 //
   2 // System.Web.UI.WebControls.Parameter
   3 //
   4 // Authors:
   5 //      Ben Maurer (bmaurer@users.sourceforge.net)
   6 //
   7 // (C) 2003 Ben Maurer
   8 //
   9
  10 #if NET_2_0
  11 using System.Collections;
  12 using System.Collections.Specialized;
  13 using System.Text;
  14 using System.Data;
  15
  16 namespace System.Web.UI.WebControls {
  17         public class Parameter : ICloneable, IStateManager {
  18
  19                 public Parameter () : base ()
  20                 {
  21                 }
  22
  23                 protected Parameter (Parameter original)
  24                 {
  25                         this.DefaultValue = original.DefaultValue;
  26                         this.Direction = original.Direction;
  27                         this.TreatEmptyStringAsNull = original.TreatEmptyStringAsNull;
  28                         this.Type = original.Type;
  29                         this.Name = original.Name;
  30                 }
  31
  32                 public Parameter (string name)
  33                 {
  34                         this.Name = name;
  35                 }
  36
  37                 public Parameter(string name, TypeCode type) : this (name)
  38                 {
  39                         this.Type = type;
  40                 }
  41
  42                 public Parameter (string name, TypeCode type, string defaultValue) : this (name, type)
  43                 {
  44                         this.DefaultValue = defaultValue;
  45                 }
  46
  47                 protected virtual Parameter Clone ()
  48                 {
  49                         return new Parameter (this);
  50                 }
  51
  52                 protected virtual object Evaluate (Control control)
  53                 {
  54                         return this.DefaultValue;
  55                 }
  56
  57                 protected void OnParameterChanged ()
  58                 {
  59                         if (_owner != null)
  60                                 _owner.CallOnParameterChanged ();
  61                 }
  62
  63                 protected virtual void LoadViewState (object savedState)
  64                 {
  65                         if (savedState == null)
  66                                 return;
  67
  68                         ViewState.LoadViewState (savedState);
  69                 }
  70
  71                 protected virtual object SaveViewState ()
  72                 {
  73                         if (viewState == null)
  74                                 return null;
  75                         return viewState.SaveViewState ();
  76                 }
  77
  78                 protected virtual void TrackViewState ()
  79                 {
  80                         isTrackingViewState = true;
  81                         if (viewState != null)
  82                                 viewState.TrackViewState ();
  83                 }
  84
  85                 object ICloneable.Clone ()
  86                 {
  87                         return this.Clone ();
  88                 }
  89
  90                 void IStateManager.LoadViewState (object savedState)
  91                 {
  92                         this.LoadViewState (savedState);
  93                 }
  94
  95                 object IStateManager.SaveViewState ()
  96                 {
  97                         return this.SaveViewState ();
  98                 }
  99
 100                 void IStateManager.TrackViewState ()
 101                 {
 102                         this.TrackViewState ();
 103                 }
 104
 105                 bool IStateManager.IsTrackingViewState {
 106                         get { return this.IsTrackingViewState; }
 107                 }
 108
 109                 [MonoTODO]
 110                 public override string ToString ()
 111                 {
 112                         return base.ToString ();
 113                 }
 114
 115                 public string DefaultValue {
 116                         get {
 117                                 return ViewState ["DefaultValue"] as string;
 118                         }
 119                         set {
 120
 121                                 if (DefaultValue != value) {
 122                                         ViewState ["DefaultValue"] = value;
 123                                         OnParameterChanged ();
 124                                 }
 125                         }
 126                 }
 127
 128                 public ParameterDirection Direction {
 129                         get {
 130                                 object o = ViewState ["Direction"];
 131                                 if (o != null)
 132                                         return (ParameterDirection) o;
 133
 134                                 return ParameterDirection.Input;
 135                         }
 136                         set {
 137
 138                                 if (Direction != value) {
 139                                         ViewState ["Direction"] = value;
 140                                         OnParameterChanged ();
 141                                 }
 142                         }
 143                 }
 144
 145
 146                 public string Name {
 147                         get {
 148                                 string s = ViewState ["Name"] as string;
 149                                 if (s != null)
 150                                         return s;
 151
 152                                 return "";
 153                         }
 154                         set {
 155
 156                                 if (Name != value) {
 157                                         ViewState ["Name"] = value;
 158                                         OnParameterChanged ();
 159                                 }
 160                         }
 161                 }
 162
 163                 public bool TreatEmptyStringAsNull {
 164                         get {
 165                                 object o = ViewState ["TreatEmptyStringAsNull"];
 166                                 if (o != null)
 167                                         return (bool) o;
 168
 169                                 return false;
 170                         }
 171                         set {
 172
 173                                 if (TreatEmptyStringAsNull != value) {
 174                                         ViewState ["TreatEmptyStringAsNull"] = value;
 175                                         OnParameterChanged ();
 176                                 }
 177                         }
 178                 }
 179
 180                 public TypeCode Type {
 181                         get {
 182                                 object o = ViewState ["Type"];
 183                                 if (o != null)
 184                                         return (TypeCode) o;
 185
 186                                 return TypeCode.Object;
 187                         }
 188                         set {
 189
 190                                 if (Type != value) {
 191                                         ViewState ["Type"] = value;
 192                                         OnParameterChanged ();
 193                                 }
 194                         }
 195                 }
 196
 197                 StateBag viewState;
 198
 199                 protected StateBag ViewState {
 200                         get {
 201                                 if (viewState == null) {
 202                                         viewState = new StateBag ();
 203                                         if (IsTrackingViewState)
 204                                                 viewState.TrackViewState ();
 205                                 }
 206                                 return viewState;
 207                         }
 208                 }
 209
 210                 bool isTrackingViewState = false;
 211                 protected bool IsTrackingViewState {
 212                         get { return isTrackingViewState; }
 213                 }
 214
 215                 private ParameterCollection _owner;
 216
 217                 internal void SetOwnerCollection (ParameterCollection own)
 218                 {
 219                         _owner = own;
 220                 }
 221
 222                 internal object ParameterValue {
 223                         get {
 224                                 object param = ViewState["ParameterValue"];
 225                                 //FIXME: need to do some null string checking magic with TreatEmptyStringAsNull here
 226                                 if (param == null)
 227                                 {
 228                                         param = DefaultValue;
 229                                         if (param == null)
 230                                         {
 231                                                 return null;
 232                                         }
 233                                 }
 234                                 return Convert.ChangeType (param, Type);
 235                         }
 236                 }
 237         }
 238 }
 239 #endif
 240