ECMA-372 Standard - C++-CLI Language Specification, First

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A parameter array is declared with a leading ... punctuator, followed by a CLI array type. There can be only one parameter array for a given function, and it shall always be the last parameter specified. The type of a parameter array is always a single-dimensional CLI array type. A caller can either pass a single argument of this CLI array type, or any number of arguments of the element type of this CLI array type. For instance, the example void F(... array^ args) { Console::WriteLine("# of arguments: {0}", args->Length); for (int i = 0; i < args->Length; i++) Console::WriteLine("\targs[{0}] = {1}", i, args[i]); } int main() { F(); F(1); F(1, 2); F(1, 2, 3); F(gcnew array {1, 2, 3, 4}); } shows a function F that takes a variable number of int arguments, and several invocations of this function.

The constructor for a delegate needs only one argument when it is bound to a static function, or a global- or namespace-scope function; the argument designates that function, using the syntax of a pointer to member or pointer to function, as appropriate. The invocation lists of two compatible delegates can be combined via the += operator, as shown. In addition, callable entities can be removed from an invocation list via the -= operator, as shown. However, an invocation list cannot be changed once it has been created.

Interfaces are implemented using inheritance syntax. interface class I1 { void F(); }; // F is implicitly virtual abstract ref struct R1 : I1 { virtual void F() { /* implement I1::F */ } }; An interface can require implementation of one or more other interfaces. For example interface class IControl { void Paint(); }; interface class ITextBox : IControl { void SetText(String^ text); }; interface class IListBox : IControl { void SetItems(array^ items); }; interface class IComboBox : ITextBox, IListBox {}; A class that implements IComboBox must also implement ITextBox, IListBox, and IControl.