Solved

Create a dynamic array in Access VBA and perform actions on it

Posted on 2010-09-09
5
815 Views
Last Modified: 2013-11-27
I would like help performing the following actions in VBA:

1. Create a dynamic array with two columns. Let’s say column A and column B

2. Add a row to the array from the current values of two variables: ProjectID and CStr(frm.Hwnd) to columns A and B respectively.

3. Search the array and retrieve the value of column B based lookup of column A

4. Delete a row in the array that has a specific value in column A

Thank you for any help on this,
Tim
0
Comment
Question by:TimJar
5 Comments
 
LVL 84

Accepted Solution

by:
Scott McDaniel (Microsoft Access MVP - EE MVE ) earned 500 total points
ID: 33636632
A Dynamic Array is one that is re-dimmed as needed:

Dim arr() as String

'/set multiple columns
Redim Preserve arr(ubound(arr)+1, 1)

arr(0, ubound(arr)) = Me.ProjectID
arr(1, ubound(arr)) = frm.Hwnd

To retrieve this:

Msgbox arr(0, <your array index>)

If you need to locate that value, use a Loop:

Dim i As Integer

For i = 0 to ubound(arr,2)
  Msgbox arr(0, i) & " : " & arr(1, i)
Next i

This might help:
http://patorjk.com/programming/tutorials/vbarrays.htm
0
 
LVL 4

Expert Comment

by:r0bertdenir0
ID: 33637709
From your description - you are not just storing but searching & deleting.
A collection might be a better choice for your problem.
Maybe you should tell us a bit more about what you're trying to do...
 
0
 

Author Comment

by:TimJar
ID: 33639663
I am using Allen Browne's method of opening multiple instances of a form (frmProjects). The problem is if I click a link to open an instance of frmProject, and a form with that ProjectID is already open, it will open another instance and I have two forms open referencing the same ProjectID. I would like to keep a log of ProjectID and the corrusponding frm.Hwnd so I can check if a instance is already open and if so set focus to that open form instead of opening a new one.

If I store the data in a table it would have two fields: ProjectID and Hwnd. Then, before I open a new instance, I will dlookup("Hwnd","tableName","ProjectID=" & "ProjectID I'm trying to open") to see if I should go to that form based on the frm.Hwnd or open a new one.

I would have to append to this table when I open a new instance and delete a record when I close an instance.

It seems to me it would be better to use an array for this instead of a table. I haven't thought about how to use a collection
0
 
LVL 31

Expert Comment

by:Helen_Feddema
ID: 33639938
Sometimes it is useful to write data to a temp table, so it can examined in the interface.
0
 
LVL 31

Expert Comment

by:Helen_Feddema
ID: 33639945
If you are going to use DLookup, I think you will need to save the data to a table.
0

Featured Post

Back Up Your Microsoft Windows Server®

Back up all your Microsoft Windows Server – on-premises, in remote locations, in private and hybrid clouds. Your entire Windows Server will be backed up in one easy step with patented, block-level disk imaging. We achieve RTOs (recovery time objectives) as low as 15 seconds.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Regardless of which version on MS Access you are using, one of the harder data-entry forms to create is one where most data from previous entries needs to be appended to new records, especially when there are numerous fields and records involved.  W…
Phishing attempts can come in all forms, shapes and sizes. No matter how familiar you think you are with them, always remember to take extra precaution when opening an email with attachments or links.
Show developers how to use a criteria form to limit the data that appears on an Access report. It is a common requirement that users can specify the criteria for a report at runtime. The easiest way to accomplish this is using a criteria form that a…
In Microsoft Access, learn how to “cascade” or have the displayed data of one combo control depend upon what’s entered in another. Base the dependent combo on a query for its row source: Add a reference to the first combo on the form as criteria i…

772 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question