Regarding Passing Many Parameters

public struct user
{
    public string FirstName;
    public string LastName;
    public string zilionotherproperties;
    public bool SearchByLastNameOnly;
}
public user[] GetUserData(user usr)
{
    //search for users using passed data and return an array of users.
}

Array FireEmployee(string first, string middle, string last, int id) {...}

Array FireEmployees(Employee[] unionWorkers) {...}

struct user
{
public user(string Username, string LastName)
{
    _username = Username;
}
private string _username;
public string UserName {
    get { return _username; }
}

FireEmployee(
    first: "Frank",
    middle: "",
    last: "Krueger",
    id: 338);