Compiler Error C2678

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binary 'operator' : no operator defined which takes a left-hand operand of type 'type' (or there is no acceptable conversion)

To use the operator, you must overload it for the specified type or define a conversion to a type for which the operator is defined.

C2678 can occur if you do not pin a native member before calling a member function on it.

Example

The following sample generates C2678.

// C2678.cpp
// compile with: /clr /c
struct S { int _a; };

ref class C {
public:
   void M( S param ) {
      test = param;   // C2678

      // OK
      pin_ptr<S> ptest = &test;
      *ptest = param;
   }
   S test;
};

The following sample generates C2678.

// C2678_2.cpp
// compile with: /clr:oldSyntax /c
struct S { int _a; };

__gc class C {
public:
   void M(S param) {
      test = param;   // C2678

      // OK
      S __pin* ptest = &test;
      *ptest = param;
   }

   S test;
};