mcs/class/System.Data/System.Data/XmlDiffLoader.cs

   1 //
   2 // mcs/class/System.Data/System.Data/XmlDiffLoader.cs
   3 //
   4 // Purpose: Loads XmlDiffGrams to DataSet
   5 //
   6 // class: XmlDiffLoader
   7 // assembly: System.Data.dll
   8 // namespace: System.Data
   9 //
  10 // Author:
  11 //     Ville Palo <vi64pa@koti.soon.fi>
  12 //
  13 // (c)copyright 2003 Ville Palo
  14 //
  15 using System;
  16 using System.Data;
  17 using System.Xml;
  18 using System.Xml.XPath;
  19 using System.Collections;
  20 using System.Globalization;
  21
  22 namespace System.Data {
  23
  24         internal class XmlDiffLoader
  25         {
  26
  27                 #region Fields
  28                 enum LoadType {CURRENT, BEFORE, ERROR};
  29                 private DataSet DSet;
  30                 private Hashtable DiffGrRows = new Hashtable ();
  31                 private Hashtable ErrorRows = new Hashtable ();
  32
  33                 #endregion // Fields
  34
  35                 #region ctors
  36
  37                 public XmlDiffLoader (DataSet DSet)
  38                 {
  39                         this.DSet = DSet;
  40                 }
  41
  42                 #endregion //ctors
  43
  44                 #region Public methods
  45
  46                 public void Load (XmlReader Reader)
  47                 {
  48
  49                         XmlDocument Document = XmlDataLoader.buildXmlDocument(Reader);
  50
  51                         XPathNavigator Navigator = Document.CreateNavigator ();
  52                         bool origEnforceConstraint = DSet.EnforceConstraints;
  53                         DSet.EnforceConstraints = false;
  54                         LoadBefore (Navigator);
  55                         LoadCurrent (Navigator);
  56                         LoadErrors (Navigator);
  57                         DSet.EnforceConstraints = origEnforceConstraint;
  58                 }
  59
  60                 #endregion // Public methods
  61
  62                 #region Private methods
  63
  64                 private void LoadCurrent (XPathNavigator Navigator)
  65                 {
  66                         Navigator.MoveToRoot ();
  67
  68                         if (Navigator.MoveToFirstChild ()) {
  69
  70                                 if (Navigator.Name == "diffgr:diffgram") {
  71
  72                                         if (Navigator.MoveToFirstChild ()) {
  73
  74                                                 if (Navigator.MoveToFirstChild ()) {
  75                                                         do {
  76                                                                 if (DSet.Tables.Contains (Navigator.LocalName))
  77                                                                         LoadCurrentTable(Navigator);
  78                                                                 else
  79                                                                         throw new DataException (Locale.GetText ("Cannot load diffGram. Table '" + Navigator.LocalName + "' is missing in the destination dataset"));
  80                                                         }while (Navigator.MoveToNext());
  81                                                 }
  82                                         }
  83                                 }
  84                         }
  85                 }
  86
  87                 private void LoadBefore (XPathNavigator Navigator)
  88                 {
  89                         Navigator.MoveToRoot ();
  90
  91                         if (!Navigator.MoveToFirstChild ())
  92                                 return; // FIXME: exception
  93
  94                         if (Navigator.Name != "diffgr:diffgram")
  95                                 return; // FIXME: exception
  96
  97                         if (Navigator.MoveToFirstChild ()) {
  98
  99                                 while (Navigator.Name != "diffgr:before") {
 100
 101                                         if (!Navigator.MoveToNext ()) // there is no before
 102                                                 return;
 103                                 }
 104
 105                                 if (Navigator.MoveToFirstChild ()) {
 106
 107                                         do {
 108                                                 if (DSet.Tables.Contains (Navigator.LocalName))
 109                                                         LoadBeforeTable(Navigator);
 110                                                 else
 111                                                         throw new DataException (Locale.GetText ("Cannot load diffGram. Table '" + Navigator.LocalName + "' is missing in the destination dataset"));
 112                                         } while (Navigator.MoveToNext ());
 113                                 }
 114                         }
 115                 }
 116
 117
 118                 private void LoadErrors (XPathNavigator Navigator)
 119                 {
 120                         Navigator.MoveToRoot ();
 121
 122                         if (!Navigator.MoveToFirstChild ())
 123                                 return; // FIXME: exception
 124
 125                         if (Navigator.Name != "diffgr:diffgram")
 126                                 return; // FIXME: exception
 127
 128                         if (Navigator.MoveToFirstChild ()) {
 129
 130                                 while (Navigator.Name != "diffgr:errors") {
 131                                         if (!Navigator.MoveToNext ())
 132                                                 return;
 133                                 }
 134
 135                                 if (Navigator.MoveToFirstChild ()) {
 136
 137                                         DataRow Row = null;
 138
 139                                         // find the row in 'current' section
 140                                         if (Navigator.MoveToFirstAttribute ()) {
 141
 142                                                 do {
 143                                                         if (Navigator.Name == "diffgr:id") {
 144
 145                                                                 if (ErrorRows.Contains (Navigator.Value))
 146                                                                         Row = (DataRow)ErrorRows [Navigator.Value];
 147                                                         }
 148
 149                                                 } while (Navigator.MoveToNextAttribute ());
 150
 151                                                 Navigator.MoveToParent ();
 152                                         }
 153
 154                                         if (Navigator.MoveToFirstChild ()) {
 155
 156                                                 string Error = "";
 157
 158                                                 do {
 159                                                         if (Navigator.MoveToFirstAttribute ()) {
 160                                                                 do {
 161                                                                         if (Navigator.Name == "diffgr:Error")
 162                                                                                 Error = Navigator.Value;
 163
 164                                                                 } while (Navigator.MoveToNextAttribute ());
 165
 166                                                                 Navigator.MoveToParent ();
 167                                                         }
 168
 169                                                         Row.SetColumnError (Navigator.LocalName, Error);
 170
 171                                                 } while (Navigator.MoveToNext ());
 172                                         }
 173                                 }
 174                         }
 175                 }
 176
 177                 private void LoadColumns (DataTable Table, DataRow Row, XPathNavigator Navigator, bool NewRow, LoadType loadType)
 178                 {
 179                         if (Navigator.MoveToFirstChild ()) {
 180
 181                                 do {
 182                                         if (Table.Columns.Contains (Navigator.LocalName))
 183                                                 Row [Navigator.LocalName] = Navigator.Value;
 184                                         else if (DSet.Tables.Contains (Navigator.LocalName)){
 185                                                 if (loadType == LoadType.BEFORE)
 186                                                         LoadBeforeTable(Navigator);
 187                                                 else if (loadType == LoadType.CURRENT)
 188                                                         LoadCurrentTable(Navigator);
 189                                         }
 190
 191                                 } while (Navigator.MoveToNext ());
 192
 193                                 if (NewRow)
 194                                         Table.Rows.Add (Row);
 195                         }
 196                 }
 197
 198                 private void LoadBeforeTable (XPathNavigator Navigator)
 199                 {
 200
 201                         String id = null;
 202                         DataTable Table = DSet.Tables [Navigator.LocalName];
 203                         DataRow Row = Table.NewRow ();
 204
 205                         if (Navigator.MoveToFirstAttribute ()) {
 206
 207                                 do {
 208                                         if (Navigator.Name == "diffgr:id")
 209                                                 id = Navigator.Value;
 210
 211                                 } while (Navigator.MoveToNextAttribute ());
 212
 213                                 Navigator.MoveToParent ();
 214                         }
 215
 216                         LoadColumns (Table, Row, Navigator, true, LoadType.BEFORE);
 217                         DiffGrRows.Add (id, Row); // for later use
 218                         Row.AcceptChanges ();
 219                 }
 220
 221                 private void LoadCurrentTable (XPathNavigator Navigator)
 222                 {
 223
 224                         DataTable Table = DSet.Tables [Navigator.LocalName];
 225                         DataRow Row = null;
 226                         bool NewRow = false;
 227                         bool HasErrors = false;
 228                         string id = "";
 229
 230                         if (Navigator.MoveToFirstAttribute ()) {
 231
 232                                 do {
 233                                         // Find out was there same row in 'before' section
 234                                         if (Navigator.LocalName == "id") {
 235                                                 id = Navigator.Value;
 236                                                 if (DiffGrRows.Contains (id))
 237                                                         Row = (DataRow)DiffGrRows [id];
 238
 239                                         }
 240                                         else if (Navigator.LocalName == "hasErrors" && String.Compare (Navigator.Value, "true", true) == 0)
 241                                                 HasErrors = true;
 242                                 } while (Navigator.MoveToNextAttribute ());
 243
 244                                 // back to business
 245                                 Navigator.MoveToParent ();
 246                         }
 247
 248                         if (Row == null) {
 249                                 Row = Table.NewRow ();
 250                                 NewRow = true;
 251                         }
 252
 253                         LoadColumns (Table, Row, Navigator, NewRow, LoadType.CURRENT);
 254
 255                         // back to business
 256                         Navigator.MoveToParent();
 257
 258                         if (HasErrors) // If row had errors add row to hashtable for later use
 259                                 ErrorRows.Add (id, Row);
 260
 261                 }
 262
 263
 264                 #endregion // Private methods
 265         }
 266 }