Custom Class Constructor of an Inherited List

Question

HI I have a class that inherits a List  where T the a custom class far below. The problem is creating the underlying list in the inheriting class constructor. The inheriting class is immediately below. How do I create the PerfAll List in the PerfAll constructor? Thank you Scott public class PerfAll : List PerfCategory > { private PerfAll _PerfAllCatCounters; public PerfAll() { _PerfAllCatCounters = new List PerfCategory >(); // PerfAll _All; PerfCategory _PerfCat; PerformanceCounterCategory [] _CounterCategories = PerformanceCounterCategory .GetCategories(); foreach ( PerformanceCounterCategory cat in _CounterCategories) { _PerfCat = new PerfCategory (cat.CategoryName); _All.Add(_PerfCat); } _PerfAllCatCounters = _All; } public PerfAll PerformanceAllCatCounters { get { return _PerfAllCatCounters; } } } Custom class: public class PerfCategory { private string _CategoryName; private List PerformanceCounter > _CounterList; public PerfCategory() { _CategoryName = string .Empty; _CounterList = new List PerformanceCounter >(); } public PerfCategory( string CategoryName) : this () { PerformanceCounter [] _CounterArray; _CategoryName = CategoryName; PerformanceCounterCategory _Counter = new PerformanceCounterCategory (CategoryName); _CounterArray = _Counter.GetCounters(); foreach ( PerformanceCounter counters in _CounterArray) { _CounterList.Add(counters); } } public string CategoryName { get { return _CategoryName; } set { _CategoryName = value ; } } public List PerformanceCounter > CounterList { get { return _CounterList; } } }

Afzal Pawaskar · Answer

Hi Scott You don't need to create the PerfAll List in the PerfAll constructor because the PerfAll class is actually a List itself as it inherits from List Check this out: public class PerfAll : List { //private PerfAll _PerfAllCatCounters; //No need of this as PerfAll class is actually a list itself public PerfAll() { //_PerfAllCatCounters = new List (); // // If a class Car inherits from a class Vehicle you can initialise Car car=new Vehicle() as every car is definitely a vehicle // but you cannot initialise Vehicle vehicle = new Car() as all vehicles are not neccessarily cars... //PerfAll _All; //No need of this as PerAll class is actually a list itself PerfCategory _PerfCat; PerformanceCounterCategory[] _CounterCategories = PerformanceCounterCategory.GetCategories(); foreach (PerformanceCounterCategory cat in _CounterCategories) { _PerfCat = new PerfCategory(cat.CategoryName); //_All.Add(_PerfCat); //Not needed. Same reason as above base.Add(_PerfCat); //Surprised???Remember PerfAll is a actually a list of type 'PerfCategory'... } //_PerfAllCatCounters = _All; //Not needed. Same reason as before } //public PerfAll PerformanceAllCatCounters /////////////////////////////////// //{ //Not needed. You can use: // get //PerfAll perfAll = new PerfAll(); // { //List list=perfAll; // return _PerfAllCatCounters; //in your main() method. The car // } //vehicle example applies here... //} /////////////////////////////////// } However your problem doesn't end here. You are going to face issues relating to SingleInstance and MultiInstance Category Types which I hope you can take care of...^_^

Sam Hobbs · Answer

The PerformanceCounterCategory.GetCategories Method is static. It sure appears to me that you need to make your PerfAll class static. I am not sure if a class derived from List can be static but if not then perhaps the List should be embedded in the PerfAll class instead of derived from.