Why is this an issue?
Properties provide a way to enforce encapsulation by providing
property procedures that give controlled access to Private fields. However, in classes with multiple fields, it is not unusual that copy-and-paste is used to quickly create the needed properties, which can result
in the wrong field being accessed by the property procedures.
Class C
Private _x As Integer
Private _Y As Integer
Public ReadOnly Property Y As Integer
Get
Return _x ' Noncompliant: The returned field should be '_y'
End Get
End Property
End Class
This rule raises an issue in any of these cases:
- A get procedure does not access the field with the corresponding name.
- A set procedure does not update the field with the corresponding name.
For simple properties, it is better to use auto-implemented
properties (VB.NET 10.0 or later).
Field and property names are compared as case-insensitive. All underscore characters are ignored.
How to fix it
Code examples
Noncompliant code example
Public Class Sample
Private _x As Integer
Private _y As Integer
Public Property Y As Integer
Get
Return _x ' Noncompliant: field '_y' is not used in the return value
End Get
Set(value As Integer)
_x = value ' Noncompliant: field '_y' is not updated
End Set
End Property
End Class
Compliant solution
Public Class Sample
Private _x As Integer
Private _y As Integer
Public Property Y As Integer
Get
Return _y
End Get
Set(value As Integer)
_y = value
End Set
End Property
End Class
Resources
