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

   1 //
   2 // System.Web.UI.WebControls.BoundColumn.cs
   3 //
   4 // Authors:
   5 //   Gaurav Vaish (gvaish@iitk.ac.in)
   6 //   Andreas Nahr (ClassDevelopment@A-SoftTech.com)
   7 //
   8 // (C) Gaurav Vaish (2002)
   9 // (C) 2003 Andreas Nahr
  10 //\r
  11
  12 using System;
  13 using System.ComponentModel;
  14 using System.Web;
  15 using System.Web.UI;
  16
  17 namespace System.Web.UI.WebControls
  18 {
  19         public class BoundColumn : DataGridColumn
  20         {
  21                 public static readonly string thisExpr = "!";
  22
  23                 private bool boundFieldDescriptionValid;
  24                 private string boundField;
  25                 private string formatting;
  26
  27                 private PropertyDescriptor desc;
  28
  29                 public BoundColumn(): base()
  30                 {
  31                 }
  32
  33                 public override void Initialize()
  34                 {
  35                         base.Initialize();
  36
  37                         desc       = null;
  38                         boundField = DataField;
  39                         formatting = DataFormatString;
  40                         boundFieldDescriptionValid = false;
  41                 }
  42
  43                 public override void InitializeCell(TableCell cell, int columnIndex, ListItemType itemType)
  44                 {
  45                         base.InitializeCell(cell, columnIndex, itemType);
  46
  47                         Control bindCtrl = null;
  48                         Control toAdd    = null;
  49                         switch(itemType)
  50                         {
  51                                 case ListItemType.Item : goto case ListItemType.SelectedItem;
  52                                 case ListItemType.AlternatingItem
  53                                                        : goto case ListItemType.SelectedItem;
  54                                 case ListItemType.SelectedItem
  55                                                        : if(DataField.Length != 0)
  56                                                                 bindCtrl = cell;
  57                                                          break;
  58                                 case ListItemType.EditItem
  59                                                            : if(!ReadOnly)
  60                                                              {
  61                                                                 TextBox box = new TextBox();
  62                                                                 toAdd = box;
  63                                                                 if(DataField.Length != 0)
  64                                                                         bindCtrl = box;
  65                                                              } else
  66                                                                      goto case ListItemType.SelectedItem;
  67
  68                                                              break;
  69                         }
  70                         if(toAdd != null)
  71                                 cell.Controls.Add(toAdd);
  72                         if(bindCtrl != null)
  73                                 bindCtrl.DataBinding += new EventHandler(OnDataBindColumn);
  74                         //throw new NotImplementedException();
  75                 }
  76
  77                 private void OnDataBindColumn(object sender, EventArgs e)
  78                 {
  79                         Control senderCtrl = (Control)sender;
  80                         DataGridItem item  = (DataGridItem)senderCtrl.NamingContainer;
  81                         object       data  = item.DataItem;
  82
  83                         if(!boundFieldDescriptionValid)
  84                         {
  85                                 if(boundField != BoundColumn.thisExpr)
  86                                 {
  87                                         desc = TypeDescriptor.GetProperties(data).Find(boundField, true);
  88                                         if(desc == null && !DesignMode)
  89                                         {
  90                                                 throw new HttpException(
  91                                                           HttpRuntime.FormatResourceString("File_Not_Found",
  92                                                                                            boundField));
  93                                         }
  94                                         boundFieldDescriptionValid = true;
  95                                 }
  96                         }
  97                         object value = data;
  98                         string val = String.Empty;
  99                         if(desc == null && DesignMode)
 100                         {
 101                                 throw new NotImplementedException();
 102                         } else
 103                         {
 104                                 if(desc != null)
 105                                         value = desc.GetValue(data);
 106                                 val = FormatDataValue(value);
 107                         }
 108                         if(senderCtrl is TableCell)
 109                         {
 110                                 if(val.Length == 0)
 111                                         val = "&nbsp;";
 112                                 ((TableCell)senderCtrl).Text = val;
 113                         } else
 114                         {
 115                                 ((TextBox)senderCtrl).Text = val;
 116                         }
 117                 }
 118
 119                 [DefaultValue (""), WebCategory ("Misc")]
 120                 [WebSysDescription ("The field that this column is bound to.")]
 121                 public virtual string DataField
 122                 {
 123                         get
 124                         {
 125                                 object o = ViewState["DataField"];
 126                                 if(o != null)
 127                                         return (string)o;
 128                                 return String.Empty;
 129                         }
 130                         set
 131                         {
 132                                 ViewState["DataField"] = value;
 133                                 OnColumnChanged();
 134                         }
 135                 }
 136
 137                 [DefaultValue (""), WebCategory ("Misc")]
 138                 [WebSysDescription ("A format string that is applied to the data value.")]
 139                 public virtual string DataFormatString
 140                 {
 141                         get
 142                         {
 143                                 object o = ViewState["DataFormatString"];
 144                                 if(o != null)
 145                                         return (string)o;
 146                                 return String.Empty;
 147                         }
 148                         set
 149                         {
 150                                 ViewState["DataFormatString"] = value;
 151                                 OnColumnChanged();
 152                         }
 153                 }
 154
 155                 [DefaultValue (false), WebCategory ("Misc")]
 156                 [WebSysDescription ("Determines if the databound field can only be displayed or also edited.")]
 157                 public virtual bool ReadOnly
 158                 {
 159                         get
 160                         {
 161                                 object o = ViewState["ReadOnly"];
 162                                 if(o != null)
 163                                         return (bool)o;
 164                                 return false;
 165                         }
 166                         set
 167                         {
 168                                 ViewState["ReadOnly"] = value;
 169                         }
 170                 }
 171
 172                 protected virtual string FormatDataValue(Object dataValue)
 173                 {
 174                         string retVal = String.Empty;
 175                         if(dataValue != null)
 176                         {
 177                                 if(formatting.Length == 0)
 178                                         retVal = dataValue.ToString();
 179                                 else
 180                                         retVal = String.Format(formatting, dataValue);
 181                         }
 182                         return retVal;
 183                 }
 184         }
 185 }