Question

Possible Duplicate:
Invoking methods with optional parameters through reflection
Name of the constructor arguments in c#

Right now I am constructing objects using reflection. I am using this to fill out API documentation. In many cases I want a non-default constructor, but sometimes they have optional parameters. These optional parameters need to be overridden with a new object other than the default. The problem is I cant figure out how to get them. The normal parameters are easy with constructorInfo.GetParameters(), however it seems the optional do not come back. Am I missing something here?

Sample code:

            ConstructorInfo[] constructorInfoList = type.GetConstructors(BindingFlags.Instance | BindingFlags.Public);
            foreach (ConstructorInfo constructorInfo in constructorInfoList)
            {
                var parameters = constructorInfo.GetParameters();
                if (parameters.Count() > 0)
                {

Answer: It turns out they do come back… this was user error.

Sample:

void Main()
{
    var ctors = typeof(Foo).GetConstructors();
    foreach(var ctor in ctors)
    {
        foreach(var param in ctor.GetParameters())
        {
            Console.WriteLine("Name: {0} Optional: {1}", param.Name, param.IsOptional);
        }
    }   
}

public class Foo
{
    public Foo(string option1, string option2 = "")
    {
    }
}

Output:

Name: option1 Optional: False
Name: option2 Optional: True

Answer 1

Possible duplicate. It appears that you can call the parameter, but have to set the values manually.

I found a similar problem here:

Invoking methods with optional parameters through reflection