I have often encountered an error such as "cannot convert from 'method group' to 'string'" in cases like:
var list = new List<string>();
// ... snip
list.Add(someObject.ToString);
of course there was a typo in the last line because I forgot the invocation parentheses after ToString
. The correct form would be:
var list = new List<string>();
// ... snip
list.Add(someObject.ToString()); // <- notice the parentheses
However I came to wonder what is a method group. Google isn't much of a help nor MSDN.
A method group is the name for a set of methods (that might be just one) - i.e. in theory the ToString
method may have multiple overloads (plus any extension methods): ToString()
, ToString(string format)
, etc - hence ToString
by itself is a "method group".
It can usually convert a method group to a (typed) delegate by using overload resolution - but not to a string etc; it doesn't make sense.
Once you add parentheses, again; overload resolution kicks in and you have unambiguously identified a method call.