Create a list with methods with a return value C# and optional argument C#-CodePudding

I have a list with methods that I am calling from a loop like below (with the help of a previous question: Create a list with methods with a return value C#):

string method;

var methods = new List<(Func<string> analysismethod, string caption)>
{
    (definitearticle, "Definite article"),
    (indefinitearticle, "Indefinite article"),
};
for (int i = 0; i < methods.Count(); i  )
{
    string gender = methods[i].analysismethod.Invoke();
    if (gender != "Cannot determine")
    {
        method = methods[i].caption;
        break;
    }
}

What I want to do now is to add an optional argument (a string) to each of the methods in methods (so I can reuse them for other purposes as well) like in:

definitearticle (word = default)
{
}

However, when I try add the optional argument, I get these errors:

Error   CS1950  The best overloaded Add method 'List<(Func<string> analysismethod, string caption)>.Add((Func<string> analysismethod, string caption))' for the collection initializer has some invalid arguments
Error   CS1503  Argument 1: cannot convert from '(method group, string)' to '(Func<string> analysismethod, string caption)'

How can I solve this?

edit: The reason why I want to use them with a specified string sometimes is that I sometimes want to analyse them for a specific input, whereas I sometimes just want to check for a default position in a sentence that I store in a struct:

public string indefinitearticle(string word = default)
{       
    if (word == default) 
    {
        word = AnalysisData.wordBeforeNoun;
    }

    string gender = default;
    if (word == "eine")
    {
        gender = "Fem";
    }
    else if (word == "ein")
    {
        gender = "Non fem";
    }
    
    return string.IsNullOrEmpty(gender) ? "Cannot determine" : gender;
}

CodePudding user response：

Introduce overload methods

public string DefiniteArticle(string param1, string param2)  
{
    // calculate and return "some string";
}

public string DefiniteArticle()
{
    return DefiniteArticle("default value1", "default value2");
}

Now with parameterless overload you are able to add it to the collection of Func<string> to satisfy it's type and use "original" method for other purposes.

var delagates = new Func<string>[] { DefiniteArticle }

Notice that delegate are types as any other int or string - for being able to add method to the collection of delegates method should be same type. Overload method allows us to "decorate" original method with the required delegate type