using System; /// 装箱类。 public class Class : IComparable, IComparable, IComparable> { private bool _hashcode = false; private bool _equals = false; /// 装箱对象。 public T Value { get; set; } /// public bool IsNull { get { return Value == null; } } /// public bool HasValue { get { return Value != null; } } /// 创建默认值。 public Class(T value = default, bool tryValueEquals = true, bool tryValueHashCode = true) { Value = value; _hashcode = tryValueHashCode; _equals = tryValueEquals; } /// public override int GetHashCode() { if (_hashcode && Value != null) { return Value.GetHashCode(); } return base.GetHashCode(); } /// public override bool Equals(object obj) { if (_equals) { if (Value == null && obj == null) return true; if (Value == null && obj != null) return false; if (Value != null && obj == null) return false; return Value.Equals(obj); } return base.Equals(obj); } /// public override string ToString() { if (Value == null) return null; return Value.ToString(); } /// /// /// public int CompareTo(object obj) { if (obj != null && obj is T) return CompareTo((T)obj); if (obj != null && obj is Class) return CompareTo(obj as Class); if (Value == null) throw new MissingMemberException(typeof(T).FullName, nameof(Value)); if (!(Value is IComparable)) throw new NotSupportedException(); return ((IComparable)Value).CompareTo(obj); } /// /// /// public int CompareTo(T other) { if (Value == null) throw new MissingMemberException(typeof(T).FullName, nameof(Value)); if (!(Value is IComparable)) throw new NotSupportedException(); return ((IComparable)Value).CompareTo(other); } /// /// /// public int CompareTo(Class other) { if (Value == null) throw new MissingMemberException(typeof(T).FullName, nameof(Value)); if (other == null || !other.HasValue) return 1; if (Value is IComparable) return ((IComparable)Value).CompareTo(other.Value); if (Value is IComparable) return ((IComparable)Value).CompareTo(other.Value); throw new NotSupportedException(); } }