Sorry about the vague title!

I have an class with a number of member variables (system, zone, site, ...)

public sealed class Cello
{
    public String Company;
    public String Zone;
    public String System;
    public String Site;
    public String Facility;
    public String Process;
    //...
}

I have an array of objects of this class.

private Cello[]   m_cellos = null;
// ...

I need to know whether the array contains objects with the same site but different systems, zones or companies since such a situation would be illegal. I have various other checks to make but they are all along similar lines.

The Array class has a number of functions that look promising but I am not very up on defining 'key selector' functions and things like that.

Any suggestions or pointers would be greatly appreciated.

--- Alistair.