我已经阅读了许多与C#中适当的平等相关的文章:
http://www.loganfranken.com/blog/687/overriding-equals-in-c-part-1/
如何重写 System.Object.GetHashCode 方法以获得最佳算法?
假设有以下示例类:
public class CustomData
{
public string Name { get; set;}
public IList<double> Values = new List<double>();
}
在使用.Equals()比较Values属性时,仍然是这种情况吗?下面是一个完整的相等性示例:
#region Equality
public override bool Equals(object value)
{
if(Object.ReferenceEquals(null, value)) return false; // Is null?
if (Object.ReferenceEquals(this, value)) return true; // Is the same object?
if (value.GetType() != this.GetType()) return false; // Is the same type?
return IsEqual((CustomData)value);
}
public bool Equals(CustomData obj)
{
if (Object.ReferenceEquals(null, obj)) return false; // Is null?
if (Object.ReferenceEquals(this, obj)) return true; // Is the same object?
return IsEqual(obj);
}
private bool IsEqual(CustomData obj)
{
return obj is CustomData other
&& other.Name.Equals(Name)
&& other.Values.Equals(Values);
}
public override int GetHashCode()
{
unchecked
{
// Choose large primes to avoid hashing collisions
const int HashingBase = (int) 2166136261;
const int HashingMultiplier = 16777619;
int hash = HashingBase;
hash = (hash * HashingMultiplier) ^ (!Object.ReferenceEquals(null, Name) ? Name.GetHashCode() : 0);
hash = (hash * HashingMultiplier) ^ (!Object.ReferenceEquals(null, Values) ? Values.GetHashCode() : 0);
return hash;
}
}
public static bool operator ==(CustomData obj, CustomData other)
{
if (Object.ReferenceEquals(obj, other)) return true;
if (Object.ReferenceEquals(null, obj)) return false; // Ensure that "obj" isn't null
return (obj.Equals(other));
}
public static bool operator !=(CustomData obj, CustomData other) => !(obj == other);
#endregion
other.Values.Equals(Values);
应该改为other.Values.SequenceEqual(Values);
。 - Sach