A long parameter list can indicate that a new structure should be created to wrap the numerous parameters or that the procedure is doing too many things.

Noncompliant Code Example

With a maximum number of 3 parameters:

Public Sub Foo(ByVal p1 As Integer, ByVal p2 As Integer, ByVal p3 As Integer, ByVal p4 As Integer) ' Noncompliant
  ' ...
End Sub

Public Function Bar(ByVal p1 As Integer, ByVal p2 As Integer, ByVal p3 As Integer, ByVal p4 As Integer) ' Noncompliant
  ' ...
End Function

Compliant Solution

Public Sub Foo(ByVal p1 As Integer, ByVal p2 As Integer, ByVal p3 As Integer)
  ' ...
End Sub

Public Function Bar(ByVal p1 As Integer, ByVal p2 As Integer, ByVal p3 As Integer)
  ' ...
End Function

Exceptions

Public Class BaseClass
    Public Sub New(Param1 As Integer)
        ' ...
    End Sub
End Class

Public Class DerivedClass
    Inherits BaseClass

    Public Sub New(Param1 As Integer, Param2 As Integer, Param3 As Integer, Param4 As Integer, Param5 As Long)
        MyBase.New(Param1) ' Compliant, the parameters intended for the base class constructor do not count in the sum of the parameter list.
        ' ...
    End Sub

End Class