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copied!<p>As an alternative, there <em>is</em> a way of using unmanaged C++ types in your code, but it does still involve some typing. In a VS C++ project, create your unmanaged struct:</p> <pre><code>struct Date_s { union { struct { unsigned nWeekDay : 3; // 0..7 (3 bits) unsigned nMonthDay : 6; // 0..31 (6 bits) unsigned : 0; // Force alignment to next boundary. unsigned nMonth : 5; // 0..12 (5 bits) unsigned nYear : 8; // 0..100 (8 bits) }; unsigned bob; }; }; </code></pre> <p>Now we create a managed type which wraps this structure:</p> <pre><code>public ref struct Date_ms { AutoPtr<Date_s> data; Date_ms() { data = new Date_s(); } property unsigned nWeekDay { unsigned get() { return data->nWeekDay; } void set(unsigned value) { data->nWeekDay = value; } } property unsigned nMonthDay { unsigned get() { return data->nMonthDay; } void set(unsigned value) { data->nMonthDay = value; } } property unsigned nMonth { unsigned get() { return data->nMonth; } void set(unsigned value) { data->nMonth = value; } } property unsigned nYear { unsigned get() { return data->nYear; } void set(unsigned value) { data->nYear = value; } } property unsigned bob { unsigned get() { return data->bob; } void set(unsigned value) { data->bob = value; } } }; </code></pre> <p>There's some copy and pasting to do there. There's also an external item I use here: it's <a href="http://weblogs.asp.net/kennykerr/archive/2007/03/26/AutoPtr.aspx" rel="nofollow">AutoPtr</a> from Kerr. I've also added the line <code>T* operator=(T* rhs) { return (m_ptr = rhs); }</code> to the AutoPtr code (as suggested in the comments to Kerr's post) to make the initialiser work.</p> <p>You can now use this new structure in your C# code, and everything should work as expected:</p> <pre><code>var test = new Date_ms(); test.nMonth = 3; test.nMonthDay = 28; test.nYear = 98; Console.WriteLine("{0}, {1}, {2}", test.nMonth, test.nMonthDay, test.nYear); Console.WriteLine("{0}", test.bob); </code></pre> <p>results in <code>3, 28, 98</code> and <code>224</code>.</p> <h1>BIG GIANT WARNING</h1> <p>Mixing managed and unmanaged code like this is dangerous, which is why Kerr wrote AutoPtr in the first place (BTW, his <a href="http://weblogs.asp.net/kennykerr/archive/2005/07/12/Mixing-Native-and-Managed-Types-in-C_2B002B00_.aspx" rel="nofollow">blog post</a> on the topic is well worth a read). This works for me, but I can't guarantee that it won't cause memory leaks. You should <em>definately</em> check that this works as intended before deploying it. </p>

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