Free Games

using System;
using System.Runtime.InteropServices;
using System.Collections.Generic;
using System.Text;

namespace SmartDeviceProject5
{
 class Program
 {
 static void Main(string[] args)
 {
 Foo foo = new Foo();
 try
 {
 SomeMethod(foo); // KABOOM! NotSupportedException
 }
 catch (Exception e)
 {
 }
 try
 {
 AnotherMethod("hello"); // KABOOM! NotSupportedException
 }
 catch (Exception e)
 {
 }
 }

 [DllImport("SomeDLL")]
 extern static void SomeMethod(Foo foo);

 [DllImport("SomeDLL")]
 extern static void AnotherMethod([MarshalAs(UnmanagedType.LPStr)] string someString);
 }

 public struct Foo
 {
 public string Bar;
 public string Borked;
 }

}

 [DllImport("SomeDLL")]
 extern static void AnotherMethod([MarshalAs(UnmanagedType.LPWStr)] string someString);
}

public struct Foo
{
 [MarshalAs(UnmanagedType.LPWStr)]
 public string Bar;
 [MarshalAs(UnmanagedType.LPWStr)]
 public string Borked;
}

using System; using System.Collections.Generic; using System.Text; using System.Runtime.InteropServices; using System.Reflection; namespace System.Runtime.InteropServices { /// <summary> /// .NET Compact framework does not support marshalling strings to ascii. /// Need to do it manually. /// </summary> static class MarshalAnsi { /// <summary> /// This Dictionary maintains all the strings allocated by an IntPtr that a structure /// was Marshalled to. /// </summary> static Dictionary<IntPtr, List<IntPtr>> myStringsForObject = new Dictionary<IntPtr,List<IntPtr>>(); public static IntPtr StructureToPtr(object structure) { Type type = structure.GetType(); var fieldInfos = type.GetFields(BindingFlags.Instance | BindingFlags.GetField | BindingFlags.Public | BindingFlags.NonPublic); // determine the total size of the structure. Need to special case strings and bools int totalSize = 0; foreach (FieldInfo field in fieldInfos) { totalSize += field.FieldType == typeof(string) ? Marshal.SizeOf(typeof(IntPtr)) : field.FieldType == typeof(bool) ? Marshal.SizeOf(typeof(int)) : Marshal.SizeOf(field.FieldType); } // allocate the pointer, and create its list of allocated strings IntPtr ret = Marshal.AllocHGlobal(totalSize); List<IntPtr> strings = new List<IntPtr>(); myStringsForObject.Add(ret, strings); // structure pointer offset, which is incremented as we write to the structure int ofs = 0; foreach (FieldInfo field in fieldInfos) { object toWrite = null; if (field.FieldType == typeof(string)) { // allocate memory for the string if need be, and add it to the // pointers string allocation list string str = field.GetValue(structure) as string; IntPtr strPtr; if (str == null) strPtr = IntPtr.Zero; else { byte[] bytes = Encoding.ASCII.GetBytes(str); strPtr = Marshal.AllocHGlobal(bytes.Length + 2); strings.Add(strPtr); Marshal.Copy(bytes, 0, strPtr, bytes.Length); Marshal.WriteInt16(strPtr, bytes.Length, 0); } toWrite = strPtr; } else if (field.FieldType == typeof(bool)) { // need to write this as an int, not a bool. // BOOL in C/C++ is really an int, which is of size 4. toWrite = (bool)field.GetValue(structure) ? 1 : 0; } else { // just do the default behavior toWrite = field.GetValue(structure); } Marshal.StructureToPtr(toWrite, (IntPtr)((int)ret + ofs), false); // increment the structure pointer offset ofs += Marshal.SizeOf(toWrite); } return ret; } /// <summary> /// Destroy the memory allocated by a structure, and all strings as well. /// </summary> /// <param name="ptr"></param> public static void DestroyStructure(IntPtr ptr) { List<IntPtr> strings = myStringsForObject[ptr]; myStringsForObject.Remove(ptr); foreach (IntPtr strPtr in strings) { Marshal.FreeHGlobal(strPtr); } Marshal.FreeHGlobal(ptr); } } }