mcs/class/System.Web/System.Web.UI/ControlCollection.cs

   1 //
   2 // System.Web.UI.ControlCollection.cs
   3 //
   4 // Authors:
   5 //      Duncan Mak  (duncan@ximian.com)
   6 //      Gonzalo Paniagua Javier (gonzalo@novell.com)
   7 //
   8 // Copyright (c) 2002-2004 Novell, Inc. (http://www.novell.com)
   9 //
  10
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System;
  33 using System.Collections;
  34
  35 namespace System.Web.UI {
  36
  37         public class ControlCollection : ICollection, IEnumerable
  38         {
  39                 Control owner;
  40                 Control [] controls;
  41                 int version;
  42                 int count;
  43                 bool readOnly;
  44
  45                 public ControlCollection (Control owner)
  46                 {
  47                         if (owner == null)
  48                                 throw new ArgumentException ("owner");
  49
  50                         this.owner = owner;
  51                 }
  52
  53                 public int Count {
  54                         get { return count; }
  55                 }
  56
  57                 public bool IsReadOnly {
  58                         get { return readOnly; }
  59                 }
  60
  61                 public bool  IsSynchronized {
  62                         get { return false; }
  63                 }
  64
  65                 public virtual Control this [int index] {
  66                         get {
  67                                 if (index < 0 || index >= count)
  68                                         throw new ArgumentOutOfRangeException ("index");
  69
  70                                 return controls [index];
  71                         }
  72                 }
  73
  74                 protected Control Owner {
  75                         get { return owner; }
  76                 }
  77
  78                 public object SyncRoot {
  79                         get { return this; }
  80                 }
  81
  82                 void EnsureControls ()
  83                 {
  84                         if (controls == null) {
  85                                 controls = new Control [5];
  86                         } else if (controls.Length < count + 1) {
  87                                 int n = controls.Length == 5 ? 3 : 2;
  88                                 Control [] newControls = new Control [controls.Length * n];
  89                                 Array.Copy (controls, 0, newControls, 0, controls.Length);
  90                                 controls = newControls;
  91                         }
  92                 }
  93
  94                 public virtual void Add (Control child)
  95                 {
  96                         if (child == null)
  97                                 throw new ArgumentNullException ();
  98
  99                         if (readOnly)
 100                                 throw new HttpException ();
 101
 102                         EnsureControls ();
 103                         version++;
 104                         controls [count++] = child;
 105                         owner.AddedControl (child, count - 1);
 106                 }
 107
 108                 public virtual void AddAt (int index, Control child)
 109                 {
 110                         if (child == null) // maybe we should check for ! (child is Control)?
 111                                 throw new ArgumentNullException ();
 112
 113                         if (index < -1 || index > count)
 114                                 throw new ArgumentOutOfRangeException ();
 115
 116                         if (readOnly)
 117                                 throw new HttpException ();
 118
 119                         if (index == -1) {
 120                                 Add (child);
 121                                 return;
 122                         }
 123
 124                         EnsureControls ();
 125                         version++;
 126                         Array.Copy (controls, index, controls, index + 1, count - index);
 127                         count++;
 128                         controls [index] = child;
 129                         owner.AddedControl (child, index);
 130                 }
 131
 132                 public virtual void Clear ()
 133                 {
 134                         if (controls == null)
 135                                 return;
 136
 137                         version++;
 138                         for (int i = 0; i < count; i++)
 139                                 owner.RemovedControl (controls [i]);
 140
 141                         count = 0;
 142                         if (owner != null)
 143                                 owner.ResetChildNames ();
 144                 }
 145
 146                 public virtual bool Contains (Control c)
 147                 {
 148                         return (controls != null && Array.IndexOf (controls, c) != -1);
 149                 }
 150
 151                 public void CopyTo (Array array, int index)
 152                 {
 153                         if (controls == null)
 154                                 return;
 155
 156                         controls.CopyTo (array, index);
 157                 }
 158
 159                 public IEnumerator GetEnumerator ()
 160                 {
 161                         return new SimpleEnumerator (this);
 162                 }
 163
 164                 public virtual int IndexOf (Control c)
 165                 {
 166                         if (controls == null)
 167                                 return -1;
 168
 169                         return Array.IndexOf (controls, c);
 170                 }
 171
 172                 public virtual void Remove (Control value)
 173                 {
 174                         int idx = IndexOf (value);
 175                         if (idx == -1)
 176                                 return;
 177                         RemoveAt (idx);
 178                 }
 179
 180                 public virtual void RemoveAt (int index)
 181                 {
 182                         if (readOnly)
 183                                 throw new HttpException ();
 184
 185                         version++;
 186                         Control ctrl = controls [index];
 187                         count--;
 188                         if (count - index > 0)
 189                                 Array.Copy (controls, index + 1, controls, index, count - index);
 190
 191                         controls [count] = null;
 192                         owner.RemovedControl (ctrl);
 193                 }
 194
 195                 internal void SetReadonly (bool readOnly)
 196                 {
 197                         this.readOnly = readOnly;
 198                 }
 199
 200                 // Almost the same as in ArrayList
 201                 sealed class SimpleEnumerator : IEnumerator
 202                 {
 203                         ControlCollection coll;
 204                         int index;
 205                         int version;
 206                         object currentElement;
 207
 208                         public SimpleEnumerator (ControlCollection coll)
 209                         {
 210                                 this.coll = coll;
 211                                 index = -1;
 212                                 version = coll.version;
 213                         }
 214
 215                         public bool MoveNext ()
 216                         {
 217                                 if (version != coll.version)
 218                                         throw new InvalidOperationException ("List has changed.");
 219
 220                                 if (index >= -1 && ++index < coll.Count) {
 221                                         currentElement = coll [index];
 222                                         return true;
 223                                 } else {
 224                                         index = -2;
 225                                         return false;
 226                                 }
 227                         }
 228
 229                         public object Current {
 230                                 get {
 231                                         if (index < 0)
 232                                                 throw new InvalidOperationException (index == -1 ? "Enumerator not started" : "Enumerator ended");
 233
 234                                         return currentElement;
 235                                 }
 236                         }
 237
 238                         public void Reset ()
 239                         {
 240                                 if (version != coll.version)
 241                                         throw new InvalidOperationException ("List has changed.");
 242
 243                                 index = -1;
 244                         }
 245                 }
 246         }
 247 }
 248