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Check if a string is an email address

This code returns a boolean expression that declares if a string is a valid email address or not. It returns true if the string is valid, false if not

Inputs
email as string

Returns
CheckIfEmail as boolean

Side Effects
it doesn't checks if the string actually is an email address, only if it is a valid email address.

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Public Function checkIfEmail(email As String) As Boolean
  Dim i As Integer
  Dim char As String
  Dim c() As String
  
  'checks if the string has the standard email pattern:
  If Not email Like "*@*.*" Then
   checkIfEmail = False
   Exit Function
  End If
  
  'splits the email-string with a "." delimeter and returns the subtring in the c-string array
  c = Split(email, ".", -1, vbBinaryCompare)
  
  'checks if the last substring has a length of either 2 or 3
  If Not Len(c(UBound(c))) = 3 And Not Len(c(UBound(c))) = 2 Then
   checkIfEmail = False
   Exit Function
  End If
  
  'steps through the last substring to see if it contains anything else unless characters from a to z
  For i = 1 To Len(c(UBound(c))) Step 1
   char = Mid(c(UBound(c)), i, 1)
   If Not (LCase(char) <= Chr(122)) Or Not (LCase(char) >= Chr(97)) Then
     checkIfEmail = False
     Exit Function
   End If
  Next i
  
  'steps through the whole email string to see if it contains any special characters:
  For i = 1 To Len(email) Step 1
   char = Mid(email, i, 1)
   If (LCase(char) <= Chr(122) And LCase(char) >= Chr(97)) _
     Or (char >= Chr(48) And char <= Chr(57)) _
     Or (char = ".") _
     Or (char = "@") _
     Or (char = "-") _
     Or (char = "_") Then
      checkIfEmail = True
   Else
     checkIfEmail = False
     Exit Function
   End If
  Next i
  
End Function