compare dates

My name is Lucas and I'm from Argentina, I really like your blog.
 
I have a query, I'm doing a "macro" for IDEA with visual basic, where from a base I take a field that has a date in string format I convert it to date. Then I want the user to enter a date with which to compare that data previously obtained, in order to have the base already filtered.
 
Sorry for my english.
 
I have made the following script:
 
' File - Import Assistant: Delimited Text
 
Function Test
dbName = "E070.IMD"
Client.ImportDelimFile "C:\Users\ldesimone\Desktop\Prueba\E070.txt", dbName, FALSE, "", "C:\Users\ldesimone\Desktop\Macro IDEA\Import Definitions.ILB\E070.RDF", TRUE
Client.OpenDatabase (dbName)
' Append Field
' Creamos una nueva columna fecha, virtual date para poder trabajar sobre ella.
Set db = Client.OpenDatabase("E070.IMD")
Set task = db.TableManagement
Set field = db.TableDef.NewField
field.Name = "FECHA"
field.Description = ""
field.Type = WI_VIRT_DATE
field.Equation = "@Ctod(AS4DATE; ""DD/MM/YYYY"")"
task.AppendField field
task.PerformTask
Set task = Nothing
Set db = Nothing
Set field = Nothing
 
' Data: Direct Extraction
Function DirectExtraction
'Aplicamos los filtros de tiempo para obtener el universo.
Dim fecha_inic As Date
Dim fecha_fin As Date
fecha_inic = InputBox("Ingrese fecha inicial")
fecha_fin = InputBox ("Ingrese fecha final")
Set db = Client.OpenDatabase("E070.IMD")
Set task = db.Extraction
task.IncludeAllFields
dbName = "UNIVERSO DE CAMBIOS.IMD"
'cant_reg = db.count
task.AddExtraction dbName, "", "AS4DATE>= ""fec_inic"" .AND. AS4DATE <= ""fec_final"""
task.CreateVirtualDatabase = False
task.PerformTask 1, db.Count
Set task = Nothing
Set db = Nothing
Client.OpenDatabase (dbName)
End Function
But at the time of compiling I get an error in task.PerformTask 1, db.Count, I read in another entry of your page that can be with the syntax. You could help me with my scrip, of course, thank you very much.