a) Assuming you don't want to compare the objects by their references, you should override GetHashCode
and Equals
methods of MyClass
HashSet<MyClass> myHash = new HashSet<MyClass>();
MyClass m1 = new MyClass("1", "123");
MyClass m2 = new MyClass("1", "123");
myHash.Add(m1);
bool b = myHash.Contains(m2); //true
public class MyClass
{
private string m_x;
private string m_y;
public MyClass(string x, string y)
{
m_x = x;
m_y = y;
}
public override int GetHashCode()
{
return m_x.GetHashCode() ^ m_y.GetHashCode();
}
public override bool Equals(object obj)
{
if (ReferenceEquals(this, obj)) return true;
if (obj == null) return false;
var other = obj as MyClass;
return m_x == other.m_x && m_y == other.m_y;
}
}
b) You can also use IEqualityComparer to compare your objects, But in this case you need some public properties
public class MyClass
{
public string m_x;
public string m_y;
public MyClass(string x, string y)
{
m_x = x;
m_y = y;
}
}
public class MyEqualityComparer : IEqualityComparer<MyClass>
{
public bool Equals(MyClass x, MyClass y)
{
return x.m_x == y.m_x && x.m_y == y.m_y;
}
public int GetHashCode(MyClass obj)
{
return obj.m_x.GetHashCode() ^ obj.m_y.GetHashCode();
}
}
Now, you only need to give the comparer to the HashSet's constructor
HashSet<MyClass> myHash = new HashSet<MyClass>( new MyEqualityComparer());