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    <p>You can't return an array from a function in the way you are probably thinking but you can return a pointer to the array. You will also need to return the length of the array so that you can properly marshal the data to the appropriate C# type. This requires a slight change to the function signature to instead return the information through parameters passed to the function.</p> <pre><code>extern "C" EXPORT_API bool GetCharacterPositions(CharacterInformation** data, int *length) { CharacterInformation *characterInformationArray = new CharacterInformation[arraysize]; // initialize contents of array. // ... snip ... *length = arraysize; *data = characterInformationArray; return true; } </code></pre> <p>In this case you will need to add a default constructor to <code>CharacterInformation</code> and use two-phase initialization (i.e. an <code>Init()</code> function).</p> <p>Be aware that you should not return a pointer <em>or</em> reference to a non-static local variable as the contents of the variable will be destroyed when it goes out of scope (i.e. when the function returns).</p> <p>To marshal the data you can try something like the following. This is untested but should give you a push in the right direction.</p> <pre><code>[DllImport("Dllname.dll", CallingConvention = CallingConvention.Winapi, CharSet = CharSet.Auto)] [return: MarshalAs(UnmanagedType.I1)] public static extern bool GetCharacterPositions(out IntPtr arrayPtr, out int size); public static List&lt;CharacterInformation&gt; GetCharacterPositions() { var arrayValue = IntPtr.Zero; var size = 0; var list = new List&lt;CharacterInformation&gt;(); if ( !GetCharacterPositions(out arrayValue, out size)) { return list; } var dataEntrySize = Marshal.SizeOf(typeof(CharacterInformation)); for ( var i = 0; i &lt; size; i++) { var cur = (CharacterInformation )Marshal.PtrToStructure(arrayValue, typeof(CharacterInformation )); list.Add(cur); arrayValue = new IntPtr(arrayValue.ToInt32() + dataEntrySize); } return list; } </code></pre> <p>You will need to add an additional call in order to properly delete the data in C++ otherwise you will end up with a memory leak.</p>
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    1. COOke thanks, but how can I convert this pointer to an array in C#. I tried it with Marshal.PtrToStructure but this won't work for an array. And I think I need to know the size of the array before calling GetCharacterPositions(), am I right?
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