如何在 GetHashCode
函数中处理 null 字段?
Module Module1
Sub Main()
Dim c As New Contact
Dim hash = c.GetHashCode
End Sub
Public Class Contact : Implements IEquatable(Of Contact)
Public Name As String
Public Address As String
Public Overloads Function Equals(ByVal other As Contact) As Boolean _
Implements System.IEquatable(Of Contact).Equals
Return Name = other.Name AndAlso Address = other.Address
End Function
Public Overrides Function Equals(ByVal obj As Object) As Boolean
If ReferenceEquals(Me, obj) Then Return True
If TypeOf obj Is Contact Then
Return Equals(DirectCast(obj, Contact))
Else
Return False
End If
End Function
Public Overrides Function GetHashCode() As Integer
Return Name.GetHashCode Xor Address.GetHashCode
End Function
End Class
End Module