Question

Is there a way to add optional parameters to C# 3.0 like there will be in C# 4.0? I gotta have this feature, I just can’t wait!

Edit:

If you know a work-around/hack to accomplish this, post it also. Thanks!

Answer 1

You can use an anonymous type and reflection as a workaround to named parameters:

public void Foo<T>(T parameters) {     var dict = typeof(T).GetProperties()         .ToDictionary(p => p.Name,              p => p.GetValue(parameters, null));      if (dict.ContainsKey('Message'))     {         Console.WriteLine(dict['Message']);     } } 

So now I can call Foo like this:

Foo(new { Message = 'Hello World' }); 

… and it will write my message.

Basically I’m extracting all the properties from the anonymous type that was passed, and converting them into a dictionary of string and object (the name of the property and its value).