VBA/Access RecordSet per form record problem

问题

I'm new to VBA and Access in general and ran into this problem whilst trying to use the proposed alternate implementation from another question I'd asked (DLookup in Access not running until textBox clicked on in Form)

The code below runs, the issue is that Me.Key is different for each record being displayed in the form and running this in the form open event means it grabs only the first value assigned to Me.Key from the first record. How can i make this run so that Me.Key is different for each record/line being displayed?

Dim rs As DAO.Recordset
Dim db As Database
Dim qdf As QueryDef
Dim prm As Parameter

Set db = CurrentDb
Set qdf = db.QueryDefs("[MF INCOME - STREAM MONTHLY]")
For Each prm In qdf.Parameters
    prm.Value = Eval(prm.Name)
Next prm

Set rs = qdf.OpenRecordset(dbOpenDynaset)
rs.FindFirst "[MyMonth]=10 AND [Org_Type]='" & Me.Key & "'"
Me.Oct = rs!SumVal
'...other month assignments

回答1:

I guess the Me.Key refers to a control located in the details section of your form. In this case, and in order to list all values taken by the control, you will need to browse all the records. One of the ways to do so can be:

Dim m_position as Long
for m_position = 1 to Me.recordset.recordcount
   me.seltop = m_position
   debug.print me.key
next m_position

Unfortunately your will see your screen blincker while browsing all the lines. You can off course find some 'screenFreezer' utilities for VBA on the net (there is one called LockWindowUpdate, as long as I can remember).

Another solution is to browse the clone of the underlying recordset (browsing the recordset will provoke the same screen behaviour as before). Supposing that the Me.Key control is bound to the "Key" column of the recordset, code could be:

Dim rsClone as DAO.recordset
set rsClone = Me.recordsetclone
if rsClone.EOF and rsClone.BOF then
Else
    rsClone.moveFirst
    Do while not rsClone.EOF
        debug.print rsCLone.fields("Key")
        rsClone.moveNext
    Loop
Endif
set rsClone = nothing

My favorite is the first one, with the "freeze"option added. Your code can manage the seltop and selheight values of the form. This means you can browse specifically records selected by users and/or, once all records browsed, go back to the original record selection.

EDIT:

Following @Ben's comment, I shall add that if your "myControl" control is in the details section and is unbound, you then will not be able to manage one value per row. The control will have the same value for all lines when the form is displayed as "continuous".

If your "myControl" control is bound to the "myField" field of a recordset, any of the following codes will increment "myControl" control value and "myField" field value at the same time. You will be than able to have a different value on each row:

Solution 1:

Dim m_position as Long
for m_position = 1 to Me.recordset.recordcount
   me.seltop = m_position
   me.controls("myControl") = m_position
next m_position

Solution 2:

Dim rsClone as DAO.recordset, _
    i as long

set rsClone = Me.recordsetclone
if rsClone.EOF and rsClone.BOF then
Else
    rsClone.moveFirst
    i = 1
    Do while not rsClone.EOF
        rsClone.fields("myField") = i
        rsClone.update
        rsClone.moveNext
        i = i+1
    Loop
Endif
set rsClone = nothing

回答2:

You could try the current event of the form, as suggested previously :)

回答3:

It is not at all clear what you need the parameters for in that query. I would suggest that you simply build a query without ANY parameters that includes all of the columns you need.

Then build small form based on this query. You can then drop this small form into your existing form and display the several fields of data based on the key value setting. (just ensure that you setup the link master and child settings for the sub-form). Here what a form looks like:

_{(source: shaw.ca)}

So, in the above the bill to displays the customer info based on customer id and is a related table to in invoice.

In other words to display several fields of data based on a key value from another table you don’t need to write one line of code. So this whole process and goal of yours can be done by drag and drop with the mouse. I often have something like a invoice, or purchase order and I ONLY have the customer ID. By using a sub-form I can display the whole address and several fields of data without writing any code. As you move from record to record, this whole set of fields will update and always display the correct related data.

来源：https://stackoverflow.com/questions/1479640/vba-access-recordset-per-form-record-problem

标签

sql

ms-access

vba

ms-access-2007

recordset