[Mono-dev] Key matching issue in generic Dictionary [correct message]

[Brian Crowell]

Brian Crowell wrote:
> IEquatable<T> is not enough. You need to override Object.GetHashCode() and 
> Object.Equals(). IEquatable<T> is optional, GetHashCode and Equals are mandatory.

Off the top of my head, this is the proper implementation:

class Name : IEquatable<Name>
{
  public Name(string value)
  {
   ...
  }

  public bool Equals(Name obj)
  {
   Console.WriteLine("Name.Equals(): this: " + this.value + " other: " + obj.Value);
   return this.value.Equals(obj.Value);
  }

  public string Value
  {
   get{return this.value;}
  }

  public override bool Equals( object obj ) {
    Name other = obj as Name;

    if( other == null )
      return false;

    return Equals(other);   // Calls Equals(Name obj)
  }

  public override int GetHashCode() {
    return value.GetHashCode();
  }

  // Override operator == and operator != as well;
  //   not necessary, but recommended
}