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

   1 /**\r
   2  * Namespace: System.Web.UI.WebControls\r
   3  * Class:     BaseDataList\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:  100%\r
  10  *\r
  11  * (C) Gaurav Vaish (2001)\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 abstract class BaseDataList: WebControl\r
  22         {\r
  23                 private  static readonly object SelectedIndexChangedEvent = new object();\r
  24                 internal static string          ItemCountViewStateKey     = "_!ItemCount";\r
  25                 \r
  26                 private DataKeyCollection dataKeys;\r
  27                 private object            dataSource;\r
  28                 \r
  29                 public BaseDataList() : base();\r
  30                 {\r
  31                 }\r
  32 \r
  33                 public static bool IsBindableType(Type type)\r
  34                 {\r
  35                         if(type.IsPrimitive || type == typeof(string) || type == typeof(DateTime) || type == typeof(Decimal))\r
  36                                 return true;\r
  37                         return false;\r
  38                 }\r
  39                 \r
  40                 public override void DataBind()\r
  41                 {\r
  42                         OnDataBinding(EventArgs.Empty);\r
  43                 }\r
  44                 \r
  45                 public event EventHandler SelectedIndexChanged\r
  46                 {\r
  47                         add\r
  48                         {\r
  49                                 Events.AddHandler(SelectedIndexChangedEvent, value);\r
  50                         }\r
  51                         remove\r
  52                         {\r
  53                                 Events.RemoveHandler(SelectedIndexChangedEvent, value);\r
  54                         }\r
  55                 }\r
  56                 \r
  57                 public virtual int CellPadding\r
  58                 {\r
  59                         get\r
  60                         {\r
  61                                 if(!ControlStyleCreated)\r
  62                                         retrurn -1;\r
  63                                 return ((TableStyle)ControlStyle).CellPadding;\r
  64                         }\r
  65                         set\r
  66                         {\r
  67                                 ((TableStyle)ControlStyle).CellPadding = value;\r
  68                         }\r
  69                 }\r
  70                 \r
  71                 public virtual int CellSpacing\r
  72                 {\r
  73                         get\r
  74                         {\r
  75                                 if(!ControlStyleCreated)\r
  76                                         retrurn -1;\r
  77                                 return ((TableStyle)ControlStyle).CellSpacing;\r
  78                         }\r
  79                         set\r
  80                         {\r
  81                                 ((TableStyle)ControlStyle).CellSpacing = value;\r
  82                         }\r
  83                 }\r
  84                 \r
  85                 public virtual string DataKeyField\r
  86                 {\r
  87                         get\r
  88                         {\r
  89                                 object o = ViewState["DataKeyField"];\r
  90                                 if(o!=null)\r
  91                                         return (string)o;\r
  92                                 return String.Empty;\r
  93                         }\r
  94                         set\r
  95                         {\r
  96                                 ViewState["DataKeyField"] = value;\r
  97                         }\r
  98                 }\r
  99                 \r
 100                 public DataKeyCollection DataKeys\r
 101                 {\r
 102                         get\r
 103                         {\r
 104                                 if( !(dataKeys) )\r
 105                                         dataKeys = new DataKeyCollection(DataKeysArray);\r
 106                                 return dataKeys;\r
 107                                 \r
 108                         }\r
 109                 }\r
 110                 \r
 111                 public string DataMember\r
 112                 {\r
 113                         get\r
 114                         {\r
 115                                 object o = ViewState["DataMember"];\r
 116                                 if(o!=null)\r
 117                                         return (string)o;\r
 118                                 return String.Empty;\r
 119                         }\r
 120                         set\r
 121                         {\r
 122                                 ViewState["DataMember"] = value;\r
 123                         }\r
 124                 }\r
 125                 \r
 126                 public virtual object DataSource\r
 127                 {\r
 128                         get\r
 129                         {\r
 130                                 return dataSource;\r
 131                         }\r
 132                         set\r
 133                         {\r
 134                                 if( (value) && ( value is IListSource || value is IEnumerable) )\r
 135                                 {\r
 136                                         dataSource = value;\r
 137                                 } else\r
 138                                 {\r
 139                                         throw new ArgumentException(HttpRuntime.FormatResourceString("Invalid_DataSource_Type", ID));\r
 140                                 }\r
 141                         }\r
 142                 }\r
 143 \r
 144                 public virtual GridLines GridLines\r
 145                 {\r
 146                         get\r
 147                         {\r
 148                                 if(ControlStyleCreated)\r
 149                                         return ((TableStyle)ControlStyle).GridLines;\r
 150                                 return GridLines.Both;\r
 151                         }\r
 152                         set\r
 153                         {\r
 154                                 ((TableStyle)ControlStyle).GridLines = value;\r
 155                         }\r
 156                 }\r
 157                 \r
 158                 public virtual HorizontalAlign HorizontalAlign\r
 159                 {\r
 160                         get\r
 161                         {\r
 162                                 if(ControlStyleCreated)\r
 163                                         return ((TableStyle)ControlStyle).HorizontalAlign;\r
 164                                 return HorizontalAlign.NotSet;\r
 165                         }\r
 166                         set\r
 167                         {\r
 168                                 ((TableStyle)ControlStyle).HorizontalAlign = value;\r
 169                         }\r
 170                 }\r
 171                 \r
 172                 protected ArrayList DataKeysArray\r
 173                 {\r
 174                         get\r
 175                         {\r
 176                                 object o = ViewState["DataKeys"];\r
 177                                 if(o == null)\r
 178                                 {\r
 179                                         o = new ArrayList();\r
 180                                         ViewState["DataKeys"] = o;\r
 181                                 }\r
 182                                 return (ArrayList)o;\r
 183                         }\r
 184                 }\r
 185                 \r
 186                 protected override void AddParsedSubObject(object o)\r
 187                 {\r
 188                         // Preventing literal controls from being added as children.\r
 189                 }\r
 190 \r
 191                 protected override void CreateChildControls()\r
 192                 {\r
 193                         Controls.Clear();\r
 194                         if(ViewState[ItemCountViewStateKey]!=null)\r
 195                         {\r
 196                                 CreateControlHierarchy(true);\r
 197                                 ClearChildViewState();\r
 198                         }\r
 199                 }\r
 200                 \r
 201                 protected override void OnDataBinding(EventArgs e)\r
 202                 {\r
 203                         base.OnDataBinding(e);\r
 204                         Controls.Clear();\r
 205                         ClearChildViewState();\r
 206                         CreateControlHierarchy(true);\r
 207                         ChildControlsCreated = true;\r
 208                         TrackViewState();\r
 209                 }\r
 210                 \r
 211                 protected virtual void OnSelectedIndexChanged(EventArgs e)\r
 212                 {\r
 213                         if(Events != null)\r
 214                         {\r
 215                                 EventHandler eh = (EventHandler)(Events[SelectedIndexChangedEvent]);\r
 216                                 if(eh!=null)\r
 217                                         eh(this, e);\r
 218                         }\r
 219                 }\r
 220                 \r
 221                 protected override void Render(HtmlTextWriter writer)\r
 222                 {\r
 223                         PrepareControlHierarchy();\r
 224                         base.RenderContents(writer);\r
 225                 }\r
 226                 \r
 227                 protected abstract void PrepareControlHierarchy();\r
 228                 protected abstract void CreateControlHierarchy(bool useDataSource);\r
 229         }\r
 230 }\r