C＃动态绑定和void方法调用

Question

Why does the compiler let this expression to compile while the run-time exception is inevitable?

I don't think that the Dynamic Binding should work for void methods

static void Main(string[] args)
{
    var res = Test((dynamic)"test");  // throws RuntimeBinderException exception at runtime
}

static void Test(dynamic args)
{
}

If the C# spec is referring the above expression as dynamically bound expression why doesn't the following method compile?

static dynamic DynamicMethod()
{
}

Answer 1

Test((dynamic)"abc") is evaluated in its entirety as a dynamic statement. More completely, you could have:

public static string Test(string s) { return s; }

This would be a better overload, so would be selected and executed in preference to the other method.

Or in other words: it can't know whether the return is void without resolving the method-group to a particular signature. And overload resolution is by definition deferred until runtime for a dynamic invoke.

Could it do more analysis? Probably. But the specification does not require it to, so at the absolute most it could be a warning (not an error).