[RESOLVED] Class Module

[DebbieCoates]

Hi

I am creating a class module that I only want to be able to use if a particular table is within the database.

I know how I can use an exists function to do this, but I'm not sure where to put the error trapping, would it be in the class initiate event, and if so, how do I then exit the class module?

also, presuming I get a response to this, how do I mark a thread as Resolved?

Cheers

Debbie

[DebbieCoates]

Further to my above email, this is wwhat I am checking to see if the table exists

Private Sub Class_Initialize()
If TableExists("01_General_Details") = False Then

' i want some code in here to thorow me out of the class module, I'm not sure what to use to exit the class at this point.


End If
End Sub

[Ecniv]

You can declare a variable (private) at the top of the class module (under option explicit) as a boolean. This will be set on the initialise event to true if the table exists or false if it doesn't.

If you are running this in Access VBA you could use similar code to the following:

public function TestForTable(byval strTablename as string) as boolean
  dim strName as string
  On error resume next
  TestForTable = false
  strName=dbengine(0)(0).tabledefs(strTablename).name
  if err.number=0 then
     TestForTable=True
  else
     err.clear
  end if

You'd need ADOx if you prefer ADO, and check a schema for the table name.


As to resolving posts, it has been made easier.
On viewing the thread, look up to the first bar, and there should be a "thread options" to click. Click it and select "Mark Thread Resolved"

Edit:
If you are using the class from a form, you may be able to use class events and raise one. Or just set the variable (first suggestion above) and add a property that returns it, so the calling sub can check if the table exists...

[DebbieCoates]

hmmm, sort of get it. This is what I have done: but, would I then have to set the variable (BlnTableName) = equal TestForTable somewhere?

Option Compare Database
Public BlnTableName As Boolean

Public Function TestForTable(ByVal strTablename As String) As Boolean
On Error Resume Next

Dim strName As String
TestForTable = False
strName = DBEngine(0)(0).TableDefs(strTablename).Name

If Err.Number = 0 Then
TestForTable = True
Else
Err.Clear
End If

End Function

[dannymking]

Debbie,

Either set the function to private and call it within the class initilisation which will set the variable to be false.. or any easier method (and better in my eyes) is to change the funtion to a property let and change the variable to private so it is only available inside the class module. You will also need a property get so the code that is using the class module will be able to reference the value..

'in the class module put..
Private blnTableExists As Boolean
Property Get TestForTable() As Boolean
  TestForTable = blnTableExists
End Property
Property Let TestForTable(strTableName)
  On Error Resume Next
  strName = DBEngine(0)(0).TableDefs(strTablename).Name
  If Err.Number = 0 Then
    blnTableExists = True
  Else
    Err.Clear
    blnTableExists = False
  End If
End Property
 
'in the module set the reference to the class module and exit if the first property is false
Dim MyClass As New ClassName
If TestForTable("TableName") Then
  'Code to perform on success
End If
Set MyClass = Nothing 'Terminate the class

[DebbieCoates]

ahhh righ, I get it now, Thanks very much for your help x