This documentation is archived and is not being maintained.

Compiler Error C3287

Error Message

the type 'type' (return type of GetEnumerator) must have a suitable public MoveNext member function and public Current property

User-defined collection classes must contain definitions for MoveNext and Current.

See How to: Iterate Over a User-Defined Collection with for each for more information.


The following sample generates C3287.

// C3287.cpp
// compile with: /clr
using namespace System;

ref struct R {
   bool MoveNext() {
      return true;
   property Object^ Current {
      Object^ get() {
         Object ^ o = gcnew Object;
         return o;

ref struct R2 {
   R ^GetEnumerator() {
      R^ r = gcnew R;
      return r;

ref struct T {};

ref struct T2 {
   T ^GetEnumerator() {
      T^ t = gcnew T;
      return t;

int main() {
   for each (int i in gcnew T2) {}   // C3287
   for each (int i in gcnew R2) {}   // OK