public class XAField : XField

Public Class XAField
	Inherits XField

Imports System
Imports BioloMICS.BioCallback
Imports BioloMICS.SharedClasses

Public Class Program

    <STAThread()>
    Shared Sub Main()

        Dim program As New Program
        program.ChangeField()
    End Sub

    '    Write sub functions here
    Public Sub ChangeField()
        '    get the current connection
        Dim SqlCo As XConnection = Run.GetCurrentConnection()
        If SqlCo Is Nothing Then
            Return
        End If

        '    get a table from its User name
        Dim TableDef As XTableDef = SqlCo.GetTableDefByUserNameEng("Your_Table_Name")
        If TableDef Is Nothing Then '    may happen if that table doesn't exist
            Return
        End If
        '    load a A-Field from that table
        Dim FieldDefMap As New XFieldDefMap
        Dim FieldDef As XFieldDef = SqlCo.GetFieldByUserNameEng("Your_AField_Name", TableDef.Key)
        If FieldDef Is Nothing Then '    that field doesn't exist
            Return
        End If
        FieldDefMap.Add(FieldDef)

        '    load all records
        Dim Where As XWhere = XWhere.Eq("_id", 2)

        Dim RecordMap As XRecordMap = Run.LoadRecords(TableDef.Key, FieldDefMap, Where)
        If RecordMap.Count() = 0 Then
            Return  '    no record loaded: nothing else to do
        End If
        For Each Record As XRecord In RecordMap
            '    get the Field from the loaded record
            Dim Field As XAField = TryCast(Record.Fields(FieldDef.Key), XAField)
            If Field Is Nothing Then    '    this field doesn't exist or is not a A-Field
                Continue For
            End If
            '    *****    A Field    *****
            '    A field value meaning:
            '    ?    0                Unknown
            '    -                    1            Character is absent
            '                        2            (unused)
            '    w                    3
            '    -, d, w            4
            '    +                    5            Character is present
            '    +, d, w            6
            '    d                    7
            '    -, +                8

            '    change the field value: replace all 'd' by '+, d, w' for the second subfield
            If Field.Subfield(1) = 0 Then   '    d
                Field.Subfield(1) = 6       '    => +, d, w
            End If

            Record.Save(False)
        Next
    End Sub
End Class