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    <p>C++/CLI introduces managed objects, for which the pointer token * should be replaced with a ^, and a 'new' should be replaced with 'gcnew', you don't need to delete these objects when you're done with them, they'll be garbage collected, [edit] managed classes have a <strong>ref</strong> keyword in their definition [/edit].</p> <p>Wrapping the C++ <strong>MyClass</strong> class in a C++/CLI wrapper class <strong>WrapperCLass</strong> could look something like this:</p> <pre><code>#include &lt;stdio.h&gt; class MyClass { public: void ShowStuff(const wchar_t *a) { wprintf(a); } }; public ref class WrapperClass { MyClass *wrapped; public: WrapperClass() { wrapped = new MyClass; } ~WrapperClass() { delete wrapped; } void ShowStuff(IntPtr string) { wrapped-&gt;ShowStuff((const wchar_t *)string.ToPointer()); } }; </code></pre> <p>If you generate a dll with this, you'll be able to use it as a reference in your C# project and you won't have to use the factory function mechanism. In C++/CLI are available, so <strong>const wchar_t *</strong> is as wel.</p> <p>To convert a <strong>System::String</strong> to a <strong>const wchar_t *</strong> you could use something like this:</p> <pre><code>using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace Client { class Program { static void Main(string[] args) { WrapperClass w = new WrapperClass(); IntPtr tmp; w.ShowStuff(tmp = System.Runtime.InteropServices.Marshal.StringToHGlobalUni("Test")); System.Runtime.InteropServices.Marshal.FreeHGlobal(tmp); } } } </code></pre> <p>(There could very well be better ways to do this...)</p> <p>For your return type you'll have to do the conversion in your wrapper class. Make some .net collection, iterate through your vector, convert the wstring to a System::String, and add it to the .net collection, and return that.</p>
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    1. POHow to wrap a C++ class in a C based dll or a CLI based dll?
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    1. COTechnically, `ref` is not a keyword; `ref class` is one of the so called whitespaced keywords. The point is that `ref` is not modifier of `class` because `ref class` and `class` are entirely different things.
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      1. USTom Blodget
    2. COFor marshalling strings, I would probably recommend passing them into C++/CLI as `System::String^` and then using an RAII-based marshalling class. Otherwise, you get exception safety issues. Naturally, you could use `finally` here, too, but personally I find RAII much simpler.
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      1. USJoel
    3. CO@Pruyque:Thank you very much.But what if i have a dll ready and want to use it in instead of rewriting the native class inside my managed class?
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