Passing Enum Array or list to Function - vb.net

Question

I want to compare an enum array to single enum instance.
Introduction
I have a class with an enum type array\list
Public Enum InvalidEmailType
Multiple_Updates
Period_Before_At_Sign
Missing_Dot_Com
End Enum
Public Class CustomerClass
Public CustomerName As String
Public ErrorTypeList = [Enum].GetValues(GetType(InvalidEmailType))
Public ErrorDescription As String
End Class
Depending on what values are added to the list, I want to run specific code.
In order to do this I compare the entire list to a single instance:
If UpdateCustomer.MatchErrorType(customer.ErrorTypeList, InvalidEmailType.Trailing_Period) = True Then
'Run Code
End If
Inside the function I compare the entire list against the single instance.
In other words, I loop through the entire list inside the class and check if the value is there:
Public Shared Function MatchErrorType(CustomerErrortypeList As List(Of InvalidEmailType), EmailError As InvalidEmailType) As Boolean
MatchErrorType = False
Dim Found As InvalidEmailType = CustomerErrortypeList.Where(Function(match) match.ToString = EmailError.ToString).OrderByDescending(Function(match) match.ToString).FirstOrDefault()
If Found > 0 Then
MatchErrorType = True
End If
End Function
Here is the problem:
How do I declare the array\list in the function parameters?
List(Of InvalidEmailType) does not work, as I get a cast error
Unable to cast object of type 'EmailValidationReport.InvalidEmailType[]' to type 'System.Collections.Generic.List`1[EmailValidationReport.InvalidEmailType]'

Answer 1

Set ErrorTypeList to a List(of InvalidEmailType) instead of array.
Public ErrorTypeList = [Enum].GetValues(GetType(InvalidEmailType)) _
.Cast(of InvalidEmailType)().ToList()
or
Dim list = customer.ErrorTypeList.Cast(of InvalidEmailType)().ToList()
If UpdateCustomer.MatchErrorType(list, InvalidEmailType.Trailing_Period) Then
'Run Code
End If

Answer 2

Since you aren't doing anything that is specific to List or Array, you can make your method signature take in an IEnumerable instead of a List. This should be able to handle both List and Array (and a few more types as well).
Public Shared Function MatchErrorType(CustomerErrortypeList As IEnumerable(Of InvalidEmailType), EmailError As InvalidEmailType) As Boolean
Dim Found As InvalidEmailType = CustomerErrortypeList.Where(Function(match) match.ToString = EmailError.ToString).OrderByDescending(Function(match) match.ToString).FirstOrDefault()
MatchErrorType = (Found > 0)
End Function