what is a member vs. a property

oop properties member
SqlRyan picture SqlRyan · Aug 5, 2009 · Viewed 20.5k times · Source

A friend who is new to OO programming asked me the difference between a Member and Property, and I was ashamed to admit that I couldn't give him a good answer. Since properties can also be objects themselves, I was left with a general description and list of exceptions.

Can somebody please lay out a good definition of when to consider something a member vs. a property? Maybe I'm bastardizing the concept, or is it just that a member is just the internal name I use, and the property is what's exposed to other objects?

I don't think that not knowing the answer to this question has affected the quality of my programming, and it's just a semantics point, but it still bothers me that I can't explain it to him.

Answer

Jon Skeet picture Jon Skeet · Aug 5, 2009

A property is one kind of member. Others might be constructors, methods, fields, nested types, conversions, indexers etc - depending on the language/platform, of course. A lot of the time the exact meaning of terminology depends on the context.

To give a C#-specific definition, from the C# 3.0 spec, section 1.6.1:

The following table provides an overview of the kinds of members a class can contain.
(Rows for...)

  • Constants
  • Fields
  • Methods
  • Properties
  • Indexers
  • Events
  • Operators
  • Constructors
  • Destructors
  • Types

Note that that's members of a class. Different "things" have different kinds of members - in C#, an interface can't have a field as a member, for example.

Related questions

What is the difference between a field and a property?

In C#, what makes a field different from a property, and when should a field be used instead of a property?

Read More
C# : assign data to properties via constructor vs. instantiating

Supposing I have an Album class : public class Album { public string Name {get; set;} public string Artist {get; set;} public int Year {get; set;} public Album() { } public Album(string name, string artist, int year) { this.Name = name; this.Artist = artist; …

Read More
Get PHP class property by string

How do I get a property in a PHP based on a string? I'll call it magic. So what is magic? $obj->Name = 'something'; $get = $obj->Name; would be like... magic($obj, 'Name', 'something'); $get = magic($obj, 'Name');

Read More