Equality in C#

• o1.Equals(o2)     - equality
  • By default, true if o1 and o2 are created by execution of the same new
  • Can be redefined in a particular class
• Object.ReferenceEquals(o1, o2)     - identity
  • True if both o1 and o2 are null, or if they are created by execution of the same new
  • Static - cannot be redefined.
• Object.Equals(o1, o2)
  • True if Object.ReferenceEquals(o1, o2), or if o1.Equals(o2)
• o1 == o2
  • True if both o1 and o2 are null, or if they are created by execution of the same new
  • An overloadable operator

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