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    <p>In your real use-case can you simply make FunctionToBePointed a <strong>static method</strong>?</p> <pre><code>static std::string Class1::FunctionToBePointed(std::string msg) { return msg; } </code></pre> <p>If yes your code should work.</p> <p>The reason is that <strong>instance methods</strong> are implicitly called with an <strong>hidden <em>this</em> pointer</strong>, this is the <strong><em>thiscall</em> calling convention</strong>, whereas <strong>static methods</strong> simply use the <strong><em>cdecl</em> convention</strong> because they don't work on any instance.</p> <p><strong>EDIT:</strong></p> <p>A sample with <strong>Boost::bind</strong>:</p> <p>The MyClass C# class:</p> <pre><code>using System; using System.ComponentModel; public class MyClass : INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged = delegate{}; private string name; public string Name { get { return name; } set { if (name != value) { name = value; PropertyChanged(this, new PropertyChangedEventArgs("Name")); } } } } </code></pre> <p>The C++/CLI wrapper:</p> <p>Wrapper.h:</p> <pre><code>class WrapperPrivateStuff; class __declspec(dllexport) UnmanagedWrapperClass { private: WrapperPrivateStuff* _private; public: void changeIt(std::string newName); public: void WrapperMethod(boost::function&lt;std::string(std::string)&gt; GetCallBack); public: UnmanagedWrapperClass(); }; </code></pre> <p>Wrapper.cpp:</p> <pre><code>#using "MyClass.dll" #include &lt;boost/signals2.hpp&gt; #include &lt;boost/bind.hpp&gt; #include "Wrapper.h" #include &lt;msclr\auto_gcroot.h&gt; #include &lt;msclr\marshal_cppstd.h&gt; #include &lt;msclr\event.h&gt; class WrapperPrivateStuff { public: boost::signals2::signal&lt;void(std::string)&gt;signalEvent; public: msclr::auto_gcroot&lt;MyClass^&gt; a; public: void EventHandlerWrapper(System::Object^, System::ComponentModel::PropertyChangedEventArgs^ args) { this-&gt;signalEvent(msclr::interop::marshal_as&lt;std::string&gt;(a-&gt;Name)); } public: WrapperPrivateStuff() { a = gcnew MyClass(); a-&gt;PropertyChanged += MAKE_DELEGATE(System::ComponentModel::PropertyChangedEventHandler, EventHandlerWrapper); } BEGIN_DELEGATE_MAP(WrapperPrivateStuff) EVENT_DELEGATE_ENTRY(EventHandlerWrapper, System::Object^, System::ComponentModel::PropertyChangedEventArgs^) END_DELEGATE_MAP() }; void UnmanagedWrapperClass::changeIt(std::string newName) { this-&gt;_private-&gt;a-&gt;Name = msclr::interop::marshal_as&lt;System::String^&gt;(newName); } UnmanagedWrapperClass::UnmanagedWrapperClass() { this-&gt;_private = new WrapperPrivateStuff(); } void UnmanagedWrapperClass::WrapperMethod(boost::function&lt;std::string(std::string)&gt; GetCallBack) { _private-&gt;signalEvent.connect(GetCallBack); } </code></pre> <p>And the native application, test.cpp:</p> <pre><code>#include &lt;iostream&gt; #include &lt;boost/bind.hpp&gt; #include &lt;boost/function.hpp&gt; #include "Wrapper.h" class Class1 { private: std::string name; public: Class1(std::string name) : name(name) { } public: std::string FunctionToBePointed(std::string msg) { std::cout &lt;&lt; "Hey it's " &lt;&lt; name &lt;&lt; "! Got: " &lt;&lt; msg &lt;&lt; std::endl; return msg; } }; int main(void) { UnmanagedWrapperClass wrapper; Class1 class1("Ed"); wrapper.WrapperMethod(boost::bind(&amp;Class1::FunctionToBePointed, &amp;class1, _1)); wrapper.changeIt("azerty"); return 0; } </code></pre> <p>Result:</p> <pre><code>&gt;test.exe Hey it's Ed! Got: azerty </code></pre> <p>I have a more generic solution but it is really ugly. :(</p> <p>Let me know if this fix your issue...</p>
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    1. POerror C2664 cannot convert parameter 1 from 'std::string (__thiscall ClassName::* )(std::string)' to 'std::string (__cdecl *)(std::string)
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    1. POerror C2664 cannot convert parameter 1 from 'std::string (__thiscall ClassName::* )(std::string)' to 'std::string (__cdecl *)(std::string)
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    1. CO@Pragmateek...for some reasons, I can't make it static. I am familiar with this answer and syntax Sir.If u can provide me any other workaround, that would be more than helpful.
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    2. COSo I fear you can't because AFAIK pointers to functions don't carry any instance information. You'll either have to **pass the object to work on as an additional parameter** or use a **wrapper** like **std::function/boost::function** with **binding**.
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    3. COhow should i initialize function pointer with boost::bind...
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