Code Inspection: Field can be made readonly (Private Accessibility)

Category	Common Practices and Code Improvements
ID	`FieldCanBeMadeReadOnly.Local`
EditorConfig	`resharper_field_can_be_made_read_only_local_highlighting`
Default severity	Suggestion
Language	C#, VB.NET
Requires SWA	No

Say you have decided to make an immutable Person class, initialized only via the constructor. You go ahead and implement the following:

public class Person
{
  private string _name;
  private int _age;
  public Person(string name, int age)
  {
    _name = name;
    _age = age;
  }
  public override string ToString() =>
    $"Name: {_name}, Age: {_age}";
}
        

Public Class Person
	Private _name As String
	Private _age As Integer
	Public Sub New(name As String, age As Integer)
		_name = name
		_age = age
	End Sub
	Public Overrides Function ToString() As String
		Return String.Format("Name: {0}, Age: {1}", _name, _age)
	End Function
End Class
        

ReSharper can detect that the fields are only being assigned in the constructor and offers to create an additional safeguard: by marking them readonly, we get to ensure that neither this class nor its users will inadvertently assign new values to these fields.

Last modified: 15 April 2024