mcs/class/System.Data/System.Data.Common/DbEnumerator.cs

   1 //
   2 // System.Data.SqlClient.DbEnumerator.cs
   3 //
   4 // Author:
   5 //   Tim Coleman (tim@timcoleman.com)
   6 //
   7 // Copyright (C) Tim Coleman, 2002
   8 //
   9
  10 //
  11 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System;
  34 using System.Collections;
  35 using System.ComponentModel;
  36 using System.Data;
  37
  38 namespace System.Data.Common {
  39         public class DbEnumerator : IEnumerator
  40         {
  41                 #region Fields
  42
  43                 readonly IDataReader reader;
  44                 readonly bool closeReader;
  45                 readonly SchemaInfo [] schema;
  46                 readonly object [] values;
  47
  48                 #endregion // Fields
  49
  50                 #region Constructors
  51
  52                 public DbEnumerator (IDataReader reader)
  53                         : this (reader, false)
  54                 {
  55                 }
  56
  57                 public DbEnumerator (IDataReader reader, bool closeReader)
  58                 {
  59                         this.reader = reader;
  60                         this.closeReader = closeReader;
  61                         this.values = new object [reader.FieldCount];
  62                         this.schema = LoadSchema (reader);
  63                 }
  64
  65                 #endregion // Constructors
  66
  67                 #region Properties
  68
  69                 public object Current {
  70                         get {
  71                                 reader.GetValues (values);
  72                                 return new DbDataRecordImpl (schema, values);
  73                         }
  74                 }
  75
  76                 #endregion // Properties
  77
  78                 #region Methods
  79
  80                 private static SchemaInfo[] LoadSchema (IDataReader reader)
  81                 {
  82                         int fieldCount = reader.FieldCount;
  83                         SchemaInfo[] schema = new SchemaInfo [fieldCount];
  84
  85                         for(int i=0; i < fieldCount; i++) {
  86                                 SchemaInfo columnSchema = new SchemaInfo ();
  87
  88                                 columnSchema.ColumnName = reader.GetName(i);
  89                                 columnSchema.ColumnOrdinal = i;
  90                                 columnSchema.DataTypeName = reader.GetDataTypeName (i);
  91                                 columnSchema.FieldType = reader.GetFieldType (i);
  92
  93                                 schema [i] = columnSchema;
  94                         }
  95
  96                         return schema;
  97                 }
  98
  99                 public bool MoveNext ()
 100                 {
 101                         if (reader.Read ())
 102                                 return true;
 103                         if (closeReader)
 104                                 reader.Close ();
 105                         return false;
 106                 }
 107
 108                 [EditorBrowsable (EditorBrowsableState.Never)]
 109                 public void Reset ()
 110                 {
 111                         throw new NotSupportedException ();
 112                 }
 113
 114                 #endregion // Methods
 115         }
 116 }