Duck type testing with C# 4 for dynamic objects.
- by Tracker1
I'm wanting to have a simple duck typing example in C# using dynamic objects. It would seem to me, that a dynamic object should have HasValue/HasProperty/HasMethod methods with a single string parameter for the name of the value, property, or method you are looking for before trying to run against it. I'm trying to avoid try/catch blocks, and deeper reflection if possible. It just seems to be a common practice for duck typing in dynamic languages (JS, Ruby, Python etc.) that is to test for a property/method before trying to use it, then falling back to a default, or throwing a controlled exception. The example below is basically what I want to accomplish.
If the methods described above don't exist, does anyone have premade extension methods for dynamic that will do this?
Example: In JavaScript I can test for a method on an object fairly easily.
//JavaScript
function quack(duck) {
if (duck && typeof duck.quack === "function") {
return duck.quack();
}
return null; //nothing to return, not a duck
}
How would I do the same in C#?
//C# 4
dynamic Quack(dynamic duck)
{
//how do I test that the duck is not null,
//and has a quack method?
//if it doesn't quack, return null
}
