Code inspection: Field can be made readonly (non-private accessibility)
Last modified: 11 February 2024tip
Say you have decided to make a Person
class, initialized only via the constructor, but with publicly available fields. You go ahead and implement the following:
public class Person
{
public string Name;
public int Age;
public Person(string name, int age)
{
Name = name;
Age = age;
}
public override string ToString() =>
$"Name: {Name}, Age: {Age}";
}
Public Class Person
Public Name As String
Public Age As Integer
Public Sub New(name As String, age As Integer)
Me.Name = name
Me.Age = age
End Sub
Public Overrides Function ToString() As String
Return String.Format("Name: {0}, Age: {1}", Name, Age)
End Function
End Class
If solution-wide inspection is enabled, 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.
For the solution-wide inspection to work, you need to enable at least one of the following:
Simplified global usage checking: select Show unused non-private type members when solution-wide analysis is off on the page of ReSharper options Alt+R, O.
Solution-wide analysis: select Enable solution-wide analysis on the page of ReSharper options Alt+R, O.
Note that even if the reported field has no direct usages in your solution, there could be cases where it is used indirectly — for example, via reflection — or it could just be designed as public API. In all those cases, you would want to suppress the usage-checking inspection for the field in one of the following ways: