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

   1 /**\r
   2  * Namespace: System.Web.UI.WebControls\r
   3  * Class:     DataGridColumnCollection\r
   4  *\r
   5  * Author:  Gaurav Vaish\r
   6  * Maintainer: gvaish@iitk.ac.in\r
   7  * Contact: <my_scripts2001@yahoo.com>, <gvaish@iitk.ac.in>\r
   8  * Implementation: yes\r
   9  * Status:  ??%\r
  10  *\r
  11  * (C) Gaurav Vaish (2002)\r
  12  */\r
  13 \r
  14 using System;\r
  15 using System.Collections;\r
  16 using System.Web;\r
  17 using System.Web.UI;\r
  18 \r
  19 namespace System.Web.UI.WebControls\r
  20 {\r
  21         public sealed class DataGridColumnCollection : ICollection, IEnumerable, IStateManager\r
  22         {\r
  23                 private DataGrid  owner;\r
  24                 private ArrayList columns;\r
  25                 private bool      trackViewState = false;\r
  26 \r
  27                 public DataGridColumnCollection(DataGrid owner, ArrayList columns)\r
  28                 {\r
  29                         this.owner   = owner;\r
  30                         this.columns = columns;\r
  31                 }\r
  32 \r
  33                 public int Count\r
  34                 {\r
  35                         get\r
  36                         {\r
  37                                 return columns.Count;\r
  38                         }\r
  39                 }\r
  40 \r
  41                 public bool IsReadOnly\r
  42                 {\r
  43                         get\r
  44                         {\r
  45                                 return false;\r
  46                         }\r
  47                 }\r
  48 \r
  49                 public bool IsSynchronized\r
  50                 {\r
  51                         get\r
  52                         {\r
  53                                 return false;\r
  54                         }\r
  55                 }\r
  56 \r
  57                 public DataGridColumn this[int index]\r
  58                 {\r
  59                         get\r
  60                         {\r
  61                                 return (DataGridColumn)(columns[index]);\r
  62                         }\r
  63                 }\r
  64 \r
  65                 public object SyncRoot\r
  66                 {\r
  67                         get\r
  68                         {\r
  69                                 return this;\r
  70                         }\r
  71                 }\r
  72 \r
  73                 public void Add(DataGridColumn column)\r
  74                 {\r
  75                         AddAt(-1, column);\r
  76                 }\r
  77 \r
  78                 public void AddAt(int index, DataGridColumn column)\r
  79                 {\r
  80                         if(index == -1)\r
  81                         {\r
  82                                 columns.Add(column);\r
  83                         } else\r
  84                         {\r
  85                                 columns.Insert(index, column);\r
  86                         }\r
  87 \r
  88                         column.SetOwner (owner);\r
  89                         if(trackViewState)\r
  90                         {\r
  91                                 ((IStateManager)column).TrackViewState();\r
  92                         }\r
  93                         OnColumnsChanged();\r
  94                 }\r
  95 \r
  96                 internal void OnColumnsChanged()\r
  97                 {\r
  98                         if(owner != null)\r
  99                         {\r
 100                                 owner.OnColumnsChanged();\r
 101                         }\r
 102                 }\r
 103 \r
 104                 public void Clear()\r
 105                 {\r
 106                         columns.Clear();\r
 107                         OnColumnsChanged();\r
 108                 }\r
 109 \r
 110                 public void CopyTo(Array array, int index)\r
 111                 {\r
 112                         foreach(DataGridColumn current in this)\r
 113                         {\r
 114                                 array.SetValue(current, index++);\r
 115                         }\r
 116                 }\r
 117 \r
 118                 public IEnumerator GetEnumerator()\r
 119                 {\r
 120                         return columns.GetEnumerator();\r
 121                 }\r
 122 \r
 123                 public int IndexOf(DataGridColumn column)\r
 124                 {\r
 125                         if(column != null)\r
 126                         {\r
 127                                 return columns.IndexOf(column);\r
 128                         }\r
 129                         return -1;\r
 130                 }\r
 131 \r
 132                 public void Remove(DataGridColumn column)\r
 133                 {\r
 134                         if(column != null)\r
 135                         {\r
 136                                 RemoveAt(IndexOf(column));\r
 137                         }\r
 138                 }\r
 139 \r
 140                 public void RemoveAt(int index)\r
 141                 {\r
 142                         if(index >= 0 && index < columns.Count)\r
 143                         {\r
 144                                 columns.RemoveAt(index);\r
 145                                 OnColumnsChanged();\r
 146                                 return;\r
 147                         }\r
 148                         //This exception is not documented, but thrown\r
 149                         throw new ArgumentOutOfRangeException("string");\r
 150                 }\r
 151 \r
 152                 object IStateManager.SaveViewState()\r
 153                 {\r
 154                         if (columns.Count == 0)\r
 155                                 return null;\r
 156 \r
 157                         ArrayList retVal = new ArrayList (columns.Count);\r
 158                         foreach (IStateManager current in columns)\r
 159                                 retVal.Add (current.SaveViewState ());\r
 160 \r
 161                         return retVal;\r
 162                 }\r
 163 \r
 164                 void IStateManager.LoadViewState(object savedState)\r
 165                 {\r
 166                         if (savedState == null || !(savedState is ArrayList))\r
 167                                 return;\r
 168 \r
 169                         ArrayList list = (ArrayList) savedState;\r
 170                         int end = list.Count;\r
 171                         if (end != columns.Count)\r
 172                                 return;\r
 173 \r
 174                         for (int i = 0; i < end; i++) {\r
 175                                 IStateManager col = (IStateManager) columns [i];\r
 176                                 col.LoadViewState (list [i]);\r
 177                         }\r
 178                 }\r
 179 \r
 180                 void IStateManager.TrackViewState()\r
 181                 {\r
 182                         trackViewState = true;\r
 183                 }\r
 184 \r
 185                 bool IStateManager.IsTrackingViewState\r
 186                 {\r
 187                         get\r
 188                         {\r
 189                                 return trackViewState;\r
 190                         }\r
 191                 }\r
 192         }\r
 193 }\r