mcs/class/CustomMarshalers/System.Runtime.InteropServices.CustomMarshalers/EnumeratorToEnumVariantMarshaler.cs

   1 //
   2 // System.Runtime.InteropServices.CustomMarshalers.EnumeratorToEnumVariantMarshaler
   3 //
   4 // Authors:
   5 //      Martin Willemoes Hansen (mwh@sysrq.dk)
   6 //      Jonathan Chambers (joncham@gmail.com)
   7 //
   8 // (C) 2003 Martin Willemoes Hansen
   9 // (C) 2007 Jonathan Chambers
  10 //
  11
  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.Runtime.CompilerServices;
  36 using System.Runtime.InteropServices;
  37
  38 namespace System.Runtime.InteropServices.CustomMarshalers
  39 {
  40         public class EnumeratorToEnumVariantMarshaler : ICustomMarshaler
  41         {
  42                 static EnumeratorToEnumVariantMarshaler instance;
  43                 public void CleanUpManagedData (object pManagedObj) {
  44                         throw new NotImplementedException ();
  45                 }
  46
  47                 public void CleanUpNativeData (IntPtr pNativeData) {
  48                         Marshal.Release (pNativeData);
  49                 }
  50
  51                 public static ICustomMarshaler GetInstance (string pstrCookie) {
  52                         if (instance == null)
  53                                 instance = new EnumeratorToEnumVariantMarshaler ();
  54                         return instance;
  55                 }
  56
  57                 public int GetNativeDataSize () {
  58                         throw new NotImplementedException ();
  59                 }
  60
  61                 public IntPtr MarshalManagedToNative (object pManagedObj) {
  62                         throw new NotImplementedException ();
  63                 }
  64
  65                 public object MarshalNativeToManaged (IntPtr pNativeData) {
  66                         IEnumVARIANT ienumvariant = (IEnumVARIANT)Marshal.GetObjectForIUnknown (pNativeData);
  67                         VARIANTEnumerator e = new VARIANTEnumerator (ienumvariant);
  68                         return e;
  69                 }
  70
  71                 [ComImport]
  72                 [Guid ("00020404-0000-0000-C000-000000000046")]
  73                 [InterfaceType (ComInterfaceType.InterfaceIsIUnknown)]
  74                 interface IEnumVARIANT
  75                 {
  76                         [MethodImpl (MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
  77                         void Next (int celt, [MarshalAs (UnmanagedType.Struct)]out object rgvar, out uint pceltFetched);
  78                         [MethodImpl (MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
  79                         void Skip (uint celt);
  80                         [MethodImpl (MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
  81                         void Reset ();
  82                         [return: MarshalAs (UnmanagedType.Interface)]
  83                         [MethodImpl (MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
  84                         IEnumVARIANT Clone ();
  85
  86                 }
  87
  88                 class VARIANTEnumerator : IEnumerator
  89                 {
  90                         IEnumVARIANT com_enum;
  91                         object current;
  92                         public VARIANTEnumerator (IEnumVARIANT com_enum) {
  93                                 this.com_enum = com_enum;
  94                         }
  95                         #region IEnumerator Members
  96
  97                         public object Current {
  98                                 get {
  99                                         return current;
 100                                 }
 101                         }
 102
 103                         public bool MoveNext () {
 104                                 object val;
 105                                 uint fetched = 0;
 106                                 com_enum.Next (1, out val, out fetched);
 107                                 if (fetched == 0)
 108                                         return false;
 109                                 current = val;
 110                                 return true;
 111                         }
 112
 113                         public void Reset () {
 114                                 com_enum.Reset ();
 115                         }
 116
 117                         #endregion
 118                 }
 119         }
 120 }