rspec/rules/S3962/csharp/rule.adoc

The value of a ``++static readonly++`` field is computed at runtime while the value of a ``++const++`` field is calculated at compile time, which improves performance.


This rule raises an issue when a ``++static readonly++`` field is initialized with a value that is computable at compile time.


As specified by Microsoft, the list of types that can have a constant value are:


||C# type||.Net Fwk type||

|bool|System.Boolean|

|byte|System.Byte|

|sbyte|System.SByte|

|char|System.Char|

|decimal|System.Decimal|

|double|System.Double|

|float|System.Single|

|int|System.Int32|

|uint|System.UInt32|

|long|System.Int64|

|ulong|System.UInt64|

|short|System.Int16|

|ushort|System.UInt16|

|string|System.String|


== Noncompliant Code Example

----
namespace myLib
{
  public class Foo
  {
    static readonly int x = 1;  // Noncompliant
    static readonly int y = x + 4; // Noncompliant
    static readonly string s = "Bar";  // Noncompliant
  }
}
----


== Compliant Solution

----
namespace myLib
{
  public class Foo
  {
    const int x = 1;
    const int y = x + 4;
    const string s = "Bar";
  }
}
----