rspec/rules/S1479/vbnet/rule.adoc

When ``Select Case`` statements have large sets of case clauses, it is usually an attempt to map two sets of data. A ``Dictionary`` should be used instead to make the code more readable and maintainable.

== Noncompliant Code Example

With a "Maximum number of case" set to 4

----
Public Class TooManyCase

    Public Function SelectCase(Ch As Char) As Integer
        Select Case Ch
            Case "a"c
                Return 1
            Case "b"c, "c"c
                Return 2
            Case "d"c
                Return 3
            Case "e"c
                Return 4
            Case "f"c, "g"c, "h"c
                Return 5
            Case Else
                Return 6
        End Select
    End Function

End Class
----

== Compliant Solution

----
Public Class TooManyCase

    Private fMatching As New Dictionary(Of Char, Integer) From {
            {"a"c, 1}, {"b"c, 2}, {"c"c, 2}, {"d"c, 3},
            {"e"c, 4}, {"f"c, 5}, {"g"c, 5}, {"h"c, 5},
        }

    Public Function SelectCase(Ch As Char) As Integer
        Dim Value As Integer
        If fMatching.TryGetValue(Ch, Value) Then
            Return Value
        Else
            Return 6
        End If
    End Function

End Class
----

== Exceptions

This rule ignores ``Select Case``s over ``Enum``s and empty, fall-through cases.