try to use python.net as the bridge.

Pythonnet.Runtime/fieldobject.cs

@@ -0,0 +1,150 @@
+// ==========================================================================
+// This software is subject to the provisions of the Zope Public License,
+// Version 2.0 (ZPL).  A copy of the ZPL should accompany this distribution.
+// THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
+// WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
+// FOR A PARTICULAR PURPOSE.
+// ==========================================================================
+
+using System;
+using System.Collections;
+using System.Reflection;
+using System.Runtime.InteropServices;
+
+namespace Python.Runtime {
+
+    //========================================================================
+    // Implements a Python descriptor type that provides access to CLR fields.
+    //========================================================================
+
+    internal class FieldObject : ExtensionType {
+
+        FieldInfo info;
+
+        public FieldObject(FieldInfo info) : base() {
+            this.info = info;
+        }
+
+        //====================================================================
+        // Descriptor __get__ implementation. This method returns the 
+        // value of the field on the given object. The returned value
+        // is converted to an appropriately typed Python object.
+        //====================================================================
+
+        public static IntPtr tp_descr_get(IntPtr ds, IntPtr ob, IntPtr tp) {
+            FieldObject self = (FieldObject)GetManagedObject(ds);
+            Object result;
+
+            if (self == null) {
+                return IntPtr.Zero;
+            }
+
+            FieldInfo info = self.info;
+
+            if ((ob == IntPtr.Zero) || (ob == Runtime.PyNone)) {
+                if (!info.IsStatic) {
+                    Exceptions.SetError(Exceptions.TypeError, 
+                               "instance attribute must be accessed " + 
+                               "through a class instance"
+                               );
+                    return IntPtr.Zero;
+                }
+                try {
+                    result = info.GetValue(null);
+                    return Converter.ToPython(result, info.FieldType);
+                }
+                catch(Exception e) {
+                    Exceptions.SetError(Exceptions.TypeError, e.Message);
+                    return IntPtr.Zero;
+                }
+            }
+
+            try {
+                CLRObject co = (CLRObject)GetManagedObject(ob);
+                result = info.GetValue(co.inst);
+                return Converter.ToPython(result, info.FieldType);
+            }
+            catch(Exception e) {
+                Exceptions.SetError(Exceptions.TypeError, e.Message);
+                return IntPtr.Zero;
+            }
+        }
+
+        //====================================================================
+        // Descriptor __set__ implementation. This method sets the value of
+        // a field based on the given Python value. The Python value must be
+        // convertible to the type of the field.
+        //====================================================================
+
+        public static new int tp_descr_set(IntPtr ds, IntPtr ob, IntPtr val) {
+            FieldObject self = (FieldObject)GetManagedObject(ds);
+            Object newval;
+
+            if (self == null) {
+                return -1;
+            }
+
+            if (val == IntPtr.Zero) {
+                Exceptions.SetError(Exceptions.TypeError, 
+                                    "cannot delete field"
+                                    );
+                return -1;
+            }
+
+            FieldInfo info = self.info;
+
+            if (info.IsLiteral || info.IsInitOnly) {
+                Exceptions.SetError(Exceptions.TypeError, 
+                                    "field is read-only"
+                                    );
+                return -1;
+            }
+
+            bool is_static = info.IsStatic;
+
+            if ((ob == IntPtr.Zero) || (ob == Runtime.PyNone)) {
+                if (!is_static) {
+                    Exceptions.SetError(Exceptions.TypeError, 
+                               "instance attribute must be set " + 
+                               "through a class instance"
+                               );
+                    return -1;
+                }
+            }
+
+            if (!Converter.ToManaged(val, info.FieldType, out newval, 
+                                      true)) {
+                return -1;
+            }
+
+            try {
+                if (!is_static) {
+                    CLRObject co = (CLRObject)GetManagedObject(ob);
+                    info.SetValue(co.inst, newval);
+                }
+                else {
+                    info.SetValue(null, newval);
+                }
+                return 0;
+            }
+            catch(Exception e) {
+                Exceptions.SetError(Exceptions.TypeError, e.Message);
+                return -1;
+            }
+        }
+
+        //====================================================================
+        // Descriptor __repr__ implementation.
+        //====================================================================
+
+        public static IntPtr tp_repr(IntPtr ob) {
+            FieldObject self = (FieldObject)GetManagedObject(ob);
+            string s = String.Format("<field '{0}'>", self.info.Name);
+            return Runtime.PyString_FromStringAndSize(s, s.Length);
+        }
+
+    }
+
+
+}