' This class is responsible for any miscellaneous functions that don't fit into any OO definition. Typically data type conversions,

' manipulations, validation etc...

Public Class Utils

    Private Const CLASS_NAME As String = "Utils"

    '#################################################################################################################################

   ' Checks the string for a valid string object.

   ' Param: String value. The string to validate

   ' Return: Boolean. True if the value is nothing/null, empty, or zero length("")

    Public Shared Function IsNull(ByVal value As String) As Boolean

        Const METHOD_NAME As String = "IsNull"

        Try

            Return (value Is Nothing OrElsevalue.Trim().Length().Equals(0))

        Catch ex As Exception

           Log.WriteLogEntry(ex, CLASS_NAME, METHOD_NAME)

        End Try

    End Function

    '#################################################################################################################################

    ' Checks the DateTime object for a valid date

   ' Param: DateTime value. The date to validate

   ' Return: Boolean. True if the value is #12:00:00AM 0001"

    Public Shared Function IsNull(ByVal value As DateTime) As Boolean

        Const METHOD_NAME As String = "IsNull"

        Try

            Return (value.Year = 1)

        Catch ex As Exception

           Log.WriteLogEntry(ex, CLASS_NAME, METHOD_NAME)

        End Try

    End Function

    '#################################################################################################################################

    ' Checks the object for a valid value

    Public Shared Function IsNull(ByVal value As System.Object) As Boolean

        Const METHOD_NAME As String = "IsNull"

        Try

            Return (value Is Nothing OrElsevalue.ToString().Length.Equals(0))

        Catch ex As Exception

           Log.WriteLogEntry(ex, CLASS_NAME, METHOD_NAME)

        End Try

    End Function

    '#################################################################################################################################

    ' Checks the string for a valid string object, and if no valid string is present, an exception is thrown

    '#################################################################################################################################

    Public Shared Sub Assert(ByVal value As String)

       If IsNull(value) Then Throw New Exception("Parameter not initialized")

    End Sub

    Public Shared Sub Assert(ByVal value As Object)

        If value Is Nothing Then Throw New Exception("Object was null")

    End Sub

    Public Shared Sub Assert(ByVal value As Int32)

       If IsValidPk(value) = False Then Throw New Exception("Invalid integer")

    End Sub

    Public Shared Function IsValidPk(ByVal value As Int32) As Boolean

        Return (value > 0)

    End Function

    Public Shared Function IsValidDate(ByVal value As Object) As Boolean

        Try

           Dim NewValue As DateTime = System.Convert.ToDateTime(value)

            Return NewValue.Year <> 1

        Catch ex As Exception

            Return False

        End Try

    End Function

    ' Converts any member of the ICollection interface into a comma separate string of values

    Public Shared Function ConvertCollectionToCSV(ByVal Col As ICollection) As String

        Dim value As Object

        Dim Result As String

        Dim First As Boolean = True

        For Each value In Col

            If First Then

                Result = value.ToString()

                First = False

            Else

                Result += "," + value.ToString()

            End If

        Next

        Return Result

    End Function

End Class