Streamlining Form Module Code in Standalone Class Module.
The Database Compact/Repair Utility.
The 'Compact on Close' Option in Microsoft Access. When enabled under File --> Current Database --> Application Options, this feature automatically compacts the database every time you open and close it. Additionally, you can manually select the Compact/Repair option from the File menu to Compact and Repair the active database. If you need to compact an external file, you can choose the Compact and Repair option from the Database Tools Menu.
If you prefer to refrain from performing the Compact and Repair process daily, you can run the Compact/Repair Utility for multiple Databases together periodically, such as weekly or fortnightly. In this case, you can conveniently select those Databases from the Disk and add them to a ListBox, as illustrated in the form image below.
The ListBox is enabled with the Multi-select option and you may select the required databases from the list and run from the Compact/Repair Command Button. The Selected Databases will be Compacted individually and their File Size will be updated in the second column of the ListBox in Kilobytes.
The FileBrowser Control.
The 'Add Databases' Command Button opens the File Browser Dialog Control and you can select one or more Databases from your disk and add them to the ListBox.
The Compact/Repair Function Running.
The selected files from the Disk are added to the DirectoryList Table, the Source Table of the ListBox. As per your Compact/Repair schedule, you may open this Compact/Repair Utility, select the required files from the ListBox then Click on the 'Compact/Repair' Command Button.
Preparing for Compact/Repair.
In the Compact/Repair Utility Program, the Database is first backed up to a temporary location. The default Backup Path shown in the TextBox above the Command Buttons is D:\Tmp\. It is defined in the Default Value Property of the TextBox and used by the Compact/Repair Utility Program.
If you would like to take any Database Backup to a different location then change the path, like C:\Backup\ in the TextBox before running the Compact/Repair option.
If you prefer a different location permanently then open the Form in Design View, display the Property Sheet of the TextBox, and change the Default Value Property to your preferred location like D:\Backup\ and see that the last character in the path is a backslash.
Note: When the same database is compacted again the old backup file will be replaced with the new one. Till that time the Backup File will remain safe in that location.
The Compacting Procedure goes through the following steps:
- The Source File is Copied to the backup location, to keep a copy of the Database safe, before the Source file is Compacted.
The DBEngine.CompactDatabase() command is executed to perform Compact and Repair operations on the database and repairs the data if Database corruption is detected. In the event of data corruption, there is a potential risk of data loss, and the specific information regarding the errors encountered is preserved in the System Table MSysCompactErrors. To mitigate such situations, it is advisable to restore the data from previously created database backups, if available.
- All objects from the source database, including both user-created and system objects, are transferred into a new database. This new temporary database name is "db1.accdb" (or "db1.mdb" depending on the file format) and is located in the designated backup path: D:\tmp\db1.accdb. The replication process excludes the system's temporary work files, ensuring a comprehensive transfer of objects while omitting non-essential temporary data.
Deletes the Source File from its home location.
- The Compacted D:\tmp\db1.accdb file is transferred to the home location with its original Database name.
Note: The Access System goes through the same procedure, when you run the Compacting operation directly from the Access System, except the Database Backup procedure.
Streamlined VBA Coding in Standalone Class Module.
Having gained insights into the utility highlighted in the previous introduction, it is now opportune to explore the streamlined event subroutine coding procedure implemented in this specific project. The necessary VBA codes for Event Subroutines are meticulously crafted within a standalone class module, enhancing code maintenance and debugging processes. This organized code structure within the standalone Class Module facilitates easy transportation to other projects, safeguarding valuable work from being entangled with less critical code in form modules. By adopting this streamlined coding approach, the practice of reusing identical code segments across controls of the same type within the form is encouraged, eliminating the need for duplicative coding efforts.
The Command Button Wrapper Class.
There exists a singular Wrapper Class designated for the Command Button Controls, along with an additional Class Module dedicated to the Intermediary or Interface Class. The Interface Class is responsible for generating instances of the Command Button Wrapper Class and facilitating the Command Button Click Events. Customarily, a Collection Object is employed to manage all Command Button Wrapper Class instances. This arrangement allows for the monitoring and capturing of Command Button Click Events triggered within the Compact_Repair Form.
The Command Button Wrapper Class VBA Code.
Option Compare Database Option Explicit Private cmdfrm As Form Private WithEvents cmd As CommandButton Private strPath As String Private bkupPath As String Dim lst As ListBox Dim lstcount As Integer Dim xtn As String '------------------------------------------------------ 'Streamlining Form Module Code 'in Stand-alone Class Modules '------------------------------------------------------ 'Database Compact/Repair Utility 'Author: a.p.r. pillai 'Date : 20/02/2024 'Rights: All Rights(c) Reserved by www.msaccesstips.com '------------------------------------------------------ 'Form's Property GET/SET Procedures Public Property Get cmd_Frm() As Form Set cmd_Frm = cmdfrm End Property Public Property Set cmd_Frm(ByRef cfrm As Form) Set cmdfrm = cfrm End Property 'Command Button Property GET/SET Procedures Public Property Get c_cmd() As CommandButton Set c_cmd = cmd End Property Public Property Set c_cmd(ByRef pcmd As CommandButton) Set cmd = pcmd Call DefaultPath End Property 'The Click Event Subroutines Private Sub cmd_Click() On Error GoTo cmd_Click_Err Select Case cmd.Name Case "cmdQuit" If MsgBox("Close Compact_Repair Form?", vbOKCancel + vbQuestion, "cmd_Click") = vbOK Then DoCmd.Close acForm, cmdfrm.Name Exit Sub End If Case "cmdFileDialog" Call FileDialog 'Display selected Path & files cmdfrm.dbList.Requery Case "cmdCompact" Call DBPrepare Case "cmdDelete" Call DBDelete End Select cmd_Click_Exit: Exit Sub cmd_Click_Err: MsgBox Err & " : " & Err.Description, , "cmd_Click()" Resume cmd_Click_Exit End Sub Private Sub DBDelete() 'Delete the selected Items from the DirectoryList Table Dim delCount As Integer Dim j As Integer Dim k As Integer Dim DB As Database Dim dbName As String Dim msg As String Dim Rst As Recordset Dim opt As Integer On Error GoTo DBDelete_Err opt = 0 msg = "1. Delete Selected." & vbCr & vbCr _ & "2. Delete All from List." & vbCr & vbCr _ & "3. Cancel Deletion." While opt < 1 Or opt > 3 opt = InputBox(msg, "Select Option.", 3) Wend Select Case opt Case 1 GoTo Selected Case 2 msg = "Empty the Database List...?" If MsgBox(msg, vbYesNo + vbCritical, "DeleteList()") = vbNo Then Exit Sub Else DoCmd.SetWarnings False DoCmd.OpenQuery "DeleteAll_ListQ" DoCmd.SetWarnings True cmdfrm.dbList.Requery cmdfrm.cmdDelete.eabled = False Exit Sub End If Case 3 Exit Sub End Select Selected: delCount = CheckList() If delCount > 0 Then msg = "Delete " & delCount & " Items." & vbCr & vbCr & "Proceed...?" If MsgBox(msg, vbYesNo, "DBDelete()") = vbNo Then Exit Sub End If Set DB = CurrentDb Set Rst = DB.OpenRecordset("DirectoryList", dbOpenDynaset) Set lst = cmdfrm.dbList For j = 0 To lstcount If lst.Selected(j) Then dbName = lst.Column(0, j) Rst.FindFirst "Path = '" & dbName & "'" If Not Rst.NoMatch Then Rst.Delete Rst.Requery End If End If Next Rst.Close Set Rst = Nothing Set DB = Nothing lst.Requery MsgBox delCount & " Item(s) Deleted From List.", , "DBDelete()" Else MsgBox delCount & " Item(s) Selected for Deletion!", , "DBDelete()" End If DBDelete_Exit: Exit Sub DBDelete_Err: MsgBox Err & " : " & Err.Description, , "DBDelete()" Resume DBDelete_Exit End Sub Private Sub DBPrepare() 'Preparatory Procedure for Compacting 'the selected Databases individually Dim xselcount As Integer Dim dbName As String Dim ldbName As String Dim strTmp As String Dim i As Integer Dim j As Integer Dim timr As Double Dim fs, f Dim lockfile As String Dim msg As String bkupPath = cmdfrm!BackupPath 'create a Backup Folder On Error Resume Next Set fs = CreateObject("Scripting.FileSystemObject") Set f = fs.GetFolder(bkupPath) If Err = 76 Or Err > 0 Then Err.Clear fs.createfolder (bkupPath) End If On Error GoTo DBPrepare_Err 'Remove existing workfiles from backup location xselcount = CheckList() If xselcount = 0 Then msg = "Select Database(s) from List for Compacting!" MsgBox msg, , "DBPrepare()" Exit Sub End If 'Ensure selected database is not active msg = "Ensure that Selected Databases are not in Use. " _ & vbCrLf & "Proceed...?" If MsgBox(msg, vbYesNo + vbDefaultButton2 + vbQuestion, _ "DBPrepare()") = vbNo Then Exit Sub End If 'Check the selected database is active or not 'if inactive then submit it to DBCompact() Program. For j = 0 To lstcount If lst.Selected(j) Then dbName = Trim(lst.Column(0, j)) i = InStrRev(dbName, ".") xtn = Mid(dbName, i) 'extract extension lockfile = IIf(xtn = ".mdb", "ldb", "laccdb") ldbName = Left(dbName, i) ldbName = ldbName & lockfile 'for checking the presense of lock file. If Len(Dir(ldbName)) > 0 Then 'database is active MsgBox "Database: " & dbName & vbCrLf & "is active. Skipping to the Next in list." GoTo nextstep End If 'Prepare for Compacting and to display the status messages. msg = "Compact/Repair: " & dbName & vbCrLf & "Proceed...?" If MsgBox(msg, vbQuestion + vbDefaultButton2 + vbYesNo, "DBPrepare()") = vbYes Then cmdfrm.lblNote.Visible = False cmdfrm.lblStat.Caption = "Working, Please wait..." DoEvents Call DBCompact(dbName) 'Run Compacting cmdfrm.lblStat.Caption = "" DoEvents nextstep: Sleep 5 End If End If Next msg = "Selected Database(s) Compacted Successfully." MsgBox msg, , "DBPrepare()" Sleep 3 cmdfrm.lblNote.Visible = True cmdfrm.lblStat.Caption = "" strTmp = bkupPath & "db1" & xtn 'Delete the temporary file Call KillTempFile(strTmp) Set fs = Nothing Set f = Nothing Set lst = Nothing DBPrepare_Exit: Exit Sub DBPrepare_Err: MsgBox Err.Description, , "DBPrepare()" Resume DBPrepare_Exit End Sub Private Sub DBCompact(ByVal strdb As String) 'Compact/Repair Database received as Parameter Dim t As Long Dim xdir As String Dim strbk As String Dim strTmp As String Dim tmp As String Dim chkFile As String Dim msg As String On Error GoTo dbCompact_Err tmp = cmdfrm!BackupPath strTmp = tmp & "db1" & xtn chkFile = strTmp Call KillTempFile(chkFile) t = InStrRev(strdb, "\") If t > 0 Then strbk = Mid(strdb, t + 1) End If strbk = tmp & strbk chkFile = strbk Call KillTempFile(chkFile) 'Make a Copy in d:\tmp folder for safe keep msg = "Taking Backup of " & strdb & vbCrLf _ & "to " & tmp cmdfrm.lblMsg.Caption = msg DoEvents 'Take a Backup of Original File to the Backup Location FileCopy strdb, strbk msg = "Transferring Objects from " & strdb & vbCrLf _ & "to " & tmp & "db1" & xtn cmdfrm.lblMsg.Caption = msg DoEvents 'https://learn.microsoft.com/en-us/office/client-developer/access/desktop-database-reference/dbengine-compactdatabase-method-dao 'Compact Database to D:\tmp\db1.accdb DBEngine.CompactDatabase strdb, strTmp ' Delete uncompacted Database and Copy Compacted db1.mdb with ' the Original Name msg = "Creating " & strdb & " from " & tmp & "db1" & xtn cmdfrm.lblMsg.Caption = msg DoEvents 'Delete uncompacted file chkFile = strdb Call KillTempFile(chkFile) 'Create Compacted File with its original name in its home location DBEngine.CompactDatabase strTmp, strdb msg = strdb & " Compacted/Repaired Successfully." cmdfrm.lblMsg.Caption = msg DoEvents Call dbListUpdate(strdb) 'Update the DirectoryList Table dbCompact_Exit: Exit Sub dbCompact_Err: MsgBox Err & " : " & Err.Description, , "dbCompact()" Resume dbCompact_Exit End Sub Private Function CheckList() As Integer 'Take selected items Count Dim k As Integer Dim xcount As Integer On Error GoTo CheckList_Err Set lst = cmdfrm.dbList lstcount = DCount("*", "DirectoryList") xcount = 0 For k = 0 To lstcount If lst.Selected(k) Then xcount = xcount + 1 End If Next If xcount = 0 Then MsgBox "No Database(s)Selected." Exit Function End If CheckList = xcount CheckList_Exit: Exit Function CheckList_Err: MsgBox Err & ": " & Err.Description, , "CheckList()" Resume CheckList_Exit End Function Private Sub dbListUpdate(ByVal cmpPath As String) 'Update the File Size of the Database after Compacting On Error GoTo dbListUpdate_Err Dim sPath As String Dim i As Variant Dim DB As Database Dim Rst As Recordset Set DB = CurrentDb Set Rst = DB.OpenRecordset("DirectoryList", dbOpenDynaset) Rst.MoveFirst Rst.FindFirst "Path = '" & cmpPath & "'" If Not Rst.NoMatch Then sPath = Rst!Path Rst.Edit Rst!FileLengthKB = FileLen(sPath) / 1024 'Db size after compacting Rst.Update End If Rst.Close cmdfrm.dbList.Requery dbListUpdate_Exit: Set Rst = Nothing Set DB = Nothing Exit Sub dbListUpdate_Err: MsgBox Err & ": " & Err.Description, , "dbListUpdate()" Resume dbListUpdate_Exit End Sub Private Sub DefaultPath() Dim strLoc As String 'Default path for CommonDialog Control strLoc = CurrentProject.Path & "\*.accdb" strPath = strLoc 'Assign to Global Variable strPath End Sub Private Sub FileDialog() On Error GoTo cmdFileDialog_Err 'Requires reference to Microsoft Office 12.0 Object Library. Dim fDialog As Office.FileDialog Dim DB As DAO.Database Dim Rst As DAO.Recordset Dim defPath As String Dim varFile As Variant Dim strfiles As String 'Set up the File Dialog. Set fDialog = Application.FileDialog(msoFileDialogFilePicker) With fDialog 'Allow user to make multiple selections of disk files. .AllowMultiSelect = True .InitialFileName = Dir(strPath) .InitialView = msoFileDialogViewDetails 'Set the title of the dialog box. .Title = "Please select one or more files" 'Clear out the current filters, and add our own. .Filters.Clear .Filters.Add "Access Databases", "*.mdb; *.accdb" .Filters.Add "Access Projects", "*.adp" .Filters.Add "All Files", "*.*" .FilterIndex = 1 '.Execute 'Show the dialog box. If the .Show method returns True, the 'user picked at least one file. If the .Show method returns 'False, the user clicked Cancel. If .Show = True Then Set DB = CurrentDb Set Rst = DB.OpenRecordset("DirectoryList", dbOpenDynaset) 'Add all selected files to the DirectoryList Table defPath = "" For Each varFile In .SelectedItems If defPath = "" Then defPath = Left(varFile, InStrRev(varFile, "\")) defPath = defPath & "*.*" strPath = defPath End If Rst.AddNew Rst![Path] = varFile Rst![FileLengthKB] = FileLen(varFile) / 1024 Rst.Update Next cmdfrm.cmdDelete.Enabled = True Else MsgBox "You clicked Cancel in the file dialog box." End If End With cmdFileDialog_Exit: Exit Sub cmdFileDialog_Err: MsgBox Err & " : " & Err.Description, , "cmdFileDialog_Click()" Resume cmdFileDialog_Exit End Sub Private Sub KillTempFile(ByVal filename As String) On Error GoTo KillTempFile_Err 'Manage Temporary Files If Len(Dir(filename)) > 0 Then Kill filename End If KillTempFile_Exit: Exit Sub KillTempFile_Err: MsgBox Err & ": " & Err.Description, , "KillTempFile()" Resume KillTempFile_Exit End Sub
The Command Button Wrapper Class starts with the usual Properties the Form Object and Command Button Control declarations. The CommandButton Control is declared and qualified with the Keyword WithEvents for capturing the Click Events when Fired from the Form.
A few local Variables are also declared in the global area of the Class Module followed by the Form and Command Button Get/Set Property Procedures.
Despite four Command Buttons on the Form, a single Click Event Subroutine within the Command Button Wrapper Class suffices. This streamlined approach enables the capture of all four Command Button Clicks within the same Event Subroutine, allowing for the execution of their respective Event Procedures. This efficiency is achievable through the implementation of streamlined Event Procedure coding.
When examining the Event Subroutine Code in order of priority, the initial step involves adding the databases slated for the Compact/Repair procedure to the ListBox. This is accomplished through the Click Event of the Command Button labeled 'Add Databases,' with the name 'CmdFileDialog.' The Click Event, in turn, invokes the FileDialog() Subroutine. The Code Segment is given below:
Private Sub FileDialog() On Error GoTo cmdFileDialog_Err 'Requires reference to Microsoft Office 12.0 Object Library. Dim fDialog As Office.FileDialog Dim db As DAO.Database Dim rst As DAO.Recordset Dim defPath As String Dim varFile As Variant Dim strfiles As String 'Set up the File Dialog. Set fDialog = Application.FileDialog(msoFileDialogFilePicker) With fDialog 'Allow user to make multiple selections of disk files. .AllowMultiSelect = True .InitialFileName = Dir(strPath) .InitialView = msoFileDialogViewDetails 'Set the title of the dialog box. .Title = "Please select one or more files" 'Clear out the current filters, and add our own. .Filters.Clear .Filters.Add "Access Databases", "*.mdb; *.accdb" .Filters.Add "Access Projects", "*.adp" .Filters.Add "All Files", "*.*" .FilterIndex = 1 '.Execute 'Show the dialog box. If the .Show method returns True, the 'user picked at least one file. If the .Show method returns 'False, the user clicked Cancel. If .Show = True Then Set db = CurrentDb Set rst = db.OpenRecordset("DirectoryList", dbOpenDynaset) 'Add all selected files to the DirectoryList Table defPath = "" For Each varFile In .SelectedItems If defPath = "" Then defPath = Left(varFile, InStrRev(varFile, "\")) defPath = defPath & "*.*" strPath = defPath End If rst.AddNew rst![Path] = varFile rst![FileLengthKB] = FileLen(varFile) / 1024 rst.Update Next cmdfrm.cmdDelete.Enabled = True Else MsgBox "You clicked Cancel in the file dialog box." End If End With cmdFileDialog_Exit: Exit Sub cmdFileDialog_Err: MsgBox Err & " : " & Err.Description, , "cmdFileDialog_Click()" Resume cmdFileDialog_Exit End Sub
This is the same Office.FileDialog Control (the File Browser Control) and Program we used in the earlier Episode with the Title External Files' List in Hyperlinks published earlier. If you click on this link you will be directed to the specific part of the Page that gives its function details.
In this scenario, we utilize the DirectoryList Table to store the databases selected from the disk, which subsequently populate the ListBox on the Form. The table encompasses two fields: Path and FileLengthKB. The former accommodates the full pathname of the database, while the latter calculates the file size in kilobytes when added to the table. Following the Compact/Repair operations, this table undergoes updates to reflect the altered file sizes.
Users have the flexibility to select one or more databases from the list and initiate the Compact/Repair process by clicking on the designated Command Button. This action triggers the execution of the DBPrepare() Subroutine, which in turn identifies the selected database(s) in the ListBox and passes them to the DBCompact() Subroutine for the Compact/Repair operation.
The DBPrepare() Subroutine VBA Code.
Private Sub DBPrepare() 'Preparatory Procedure for Compacting 'the selected Databases individually Dim xselcount As Integer Dim dbName As String Dim ldbName As String Dim strTmp As String Dim i As Integer Dim j As Integer Dim timr As Double Dim fs, f Dim lockfile As String Dim msg As String bkupPath = cmdfrm!BackupPath 'create a Backup Folder On Error Resume Next Set fs = CreateObject("Scripting.FileSystemObject") Set f = fs.GetFolder(bkupPath) If Err = 76 Or Err > 0 Then Err.Clear fs.createfolder (bkupPath) End If On Error GoTo DBPrepare_Err 'Remove existing workfiles from backup location xselcount = CheckList() If xselcount = 0 Then msg = "Select Database(s) from List for Compacting!" MsgBox msg, , "DBPrepare()" Exit Sub End If 'Ensure selected database is not active msg = "Ensure that Selected Databases are not in Use. " _ & vbCrLf & "Proceed...?" If MsgBox(msg, vbYesNo + vbDefaultButton2 + vbQuestion, _ "DBPrepare()") = vbNo Then Exit Sub End If 'Check the selected database is active or not 'if inactive then submit it to DBCompact() Program. For j = 0 To lstcount If lst.Selected(j) Then dbName = Trim(lst.Column(0, j)) i = InStrRev(dbName, ".") xtn = Mid(dbName, i) 'extract extension lockfile = IIf(xtn = ".mdb", "ldb", "laccdb") ldbName = Left(dbName, i) ldbName = ldbName & lockfile 'for checking the presense of lock file. If Len(Dir(ldbName)) > 0 Then 'database is active MsgBox "Database: " & dbName & vbCrLf & "is active. Skipping to the Next in list." GoTo nextstep End If 'Prepare for Compacting and to display the status messages. msg = "Compact/Repair: " & dbName & vbCrLf & "Proceed...?" If MsgBox(msg, vbQuestion + vbDefaultButton2 + vbYesNo, "DBPrepare()") = vbYes Then cmdfrm.lblNote.Visible = False cmdfrm.lblStat.Caption = "Working, Please wait..." DoEvents Call DBCompact(dbName) 'Run Compacting cmdfrm.lblStat.Caption = "" DoEvents nextstep: Sleep 5 End If End If Next msg = "Selected Database(s) Compacted Successfully." MsgBox msg, , "DBPrepare()" Sleep 3 cmdfrm.lblNote.Visible = True cmdfrm.lblStat.Caption = "" strTmp = bkupPath & "db1" & xtn 'Delete the temporary file Call KillTempFile(strTmp) Set fs = Nothing Set f = Nothing Set lst = Nothing DBPrepare_Exit: Exit Sub DBPrepare_Err: MsgBox Err.Description, , "DBPrepare()" Resume DBPrepare_Exit End Sub
The above DBPrepare() Subroutine picks the User selected items individually and passes them to the actual Compacting Subroutine DBCompact() below for Compact/Repair operations and restoring the Compacted Database to its home location.
The DBCompact Subroutine VBA Code.
Private Sub DBCompact(ByVal strdb As String)
'Compact/Repair Database received as Parameter Dim t As Long Dim xdir As String Dim strbk As String Dim strTmp As String Dim tmp As String Dim chkFile As String Dim msg As String On Error GoTo dbCompact_Err tmp = cmdfrm!BackupPath strTmp = tmp & "db1" & xtn chkFile = strTmp Call KillTempFile(chkFile) t = InStrRev(strdb, "\") If t > 0 Then strbk = Mid(strdb, t + 1) End If strbk = tmp & strbk chkFile = strbk Call KillTempFile(chkFile) 'Make a Copy in d:\tmp folder for safe keep msg = "Taking Backup of " & strdb & vbCrLf _ & "to " & tmp cmdfrm.lblMsg.Caption = msg DoEvents 'Take a Backup of Original File to the Backup Location FileCopy strdb, strbk msg = "Transferring Objects from " & strdb & vbCrLf _ & "to " & tmp & "db1" & xtn cmdfrm.lblMsg.Caption = msg DoEvents 'https://learn.microsoft.com/en-us/office/client-developer/access/desktop-database-reference/dbengine-compactdatabase-method-dao 'Compact Database to D:\tmp\db1.accdb DBEngine.CompactDatabase strdb, strTmp ' Delete uncompacted Database and Copy Compacted db1.mdb with ' the Original Name msg = "Creating " & strdb & " from " & tmp & "db1" & xtn cmdfrm.lblMsg.Caption = msg DoEvents 'Delete uncompacted file chkFile = strdb Call KillTempFile(chkFile) 'Create Compacted File with its original name in its home location DBEngine.CompactDatabase strTmp, strdb msg = strdb & " Compacted/Repaired Successfully." cmdfrm.lblMsg.Caption = msg DoEvents Call dbListUpdate(strdb) 'Update the DirectoryList Table dbCompact_Exit: Exit Sub dbCompact_Err: MsgBox Err & " : " & Err.Description, , "dbCompact()" Resume dbCompact_Exit End Sub
There are three other small supporting Subroutines called from both the DBPrepare() and DBCompact() Subroutines.
The CheckList() Subroutine.
Private Function CheckList() As Integer 'Take selected items Count Dim k As Integer Dim xcount As Integer On Error GoTo CheckList_Err Set lst = cmdfrm.dbList lstcount = DCount("*", "DirectoryList") xcount = 0 For k = 0 To lstcount If lst.Selected(k) Then xcount = xcount + 1 End If Next If xcount = 0 Then MsgBox "No Database(s)Selected." Exit Function End If CheckList = xcount CheckList_Exit: Exit Function CheckList_Err: MsgBox Err & ": " & Err.Description, , "CheckList()" Resume CheckList_Exit End Function
The above Subroutine checks whether any Item is selected in the ListBox and takes its count when the 'Compact/Repair' or 'Delete from List' Command Button is Clicked. If found selected then the selected operation is performed.
The dbListUpdate() Subroutine VBA.
Private Sub dbListUpdate(ByVal cmpPath As String) 'Update the File Size of the Database after Compacting On Error GoTo dbListUpdate_Err Dim sPath As String Dim i As Variant Dim DB As Database Dim Rst As Recordset Set DB = CurrentDb Set Rst = DB.OpenRecordset("DirectoryList", dbOpenDynaset) Rst.MoveFirst Rst.FindFirst "Path = '" & cmpPath & "'" If Not Rst.NoMatch Then sPath = Rst!Path Rst.Edit Rst!FileLengthKB = FileLen(sPath) / 1024 'Db size after compacting Rst.Update End If Rst.Close cmdfrm.dbList.Requery dbListUpdate_Exit: Set Rst = Nothing Set DB = Nothing Exit Sub dbListUpdate_Err: MsgBox Err & ": " & Err.Description, , "dbListUpdate()" Resume dbListUpdate_Exit End Sub
This Program is Called from the DBCompact() Subroutine to update the File Size in Kilobytes in the ListBox after Compacting the Database.
The DBDelete() Subroutine.
Private Sub DBDelete() 'Delete the selected Items from the DirectoryList Table Dim delCount As Integer Dim j As Integer Dim k As Integer Dim DB As Database Dim dbName As String Dim msg As String Dim Rst As Recordset Dim opt As Integer On Error GoTo DBDelete_Err opt = 0 msg = "1. Delete Selected." & vbCr & vbCr _ & "2. Delete All from List." & vbCr & vbCr _ & "3. Cancel Deletion." While opt < 1 Or opt > 3 opt = InputBox(msg, "Select Option.", 3) Wend Select Case opt Case 1 GoTo Selected Case 2 msg = "Empty the Database List...?" If MsgBox(msg, vbYesNo + vbCritical, "DeleteList()") = vbNo Then Exit Sub Else DoCmd.SetWarnings False DoCmd.OpenQuery "DeleteAll_ListQ" DoCmd.SetWarnings True cmdfrm.dbList.Requery cmdfrm.cmdDelete.eabled = False Exit Sub End If Case 3 Exit Sub End Select Selected: delCount = CheckList() If delCount > 0 Then msg = "Delete " & delCount & " Items." & vbCr & vbCr & "Proceed...?" If MsgBox(msg, vbYesNo, "DBDelete()") = vbNo Then Exit Sub End If Set DB = CurrentDb Set Rst = DB.OpenRecordset("DirectoryList", dbOpenDynaset) Set lst = cmdfrm.dbList For j = 0 To lstcount If lst.Selected(j) Then dbName = lst.Column(0, j) Rst.FindFirst "Path = '" & dbName & "'" If Not Rst.NoMatch Then Rst.Delete Rst.Requery End If End If Next Rst.Close Set Rst = Nothing Set DB = Nothing lst.Requery MsgBox delCount & " Item(s) Deleted From List.", , "DBDelete()" Else MsgBox delCount & " Item(s) Selected for Deletion!", , "DBDelete()" End If DBDelete_Exit: Exit Sub DBDelete_Err: MsgBox Err & " : " & Err.Description, , "DBDelete()" Resume DBDelete_Exit End Sub
To remove some databases from the ListBox, you must select them from the ListBox and Click the 'Delete from List' Command Button. The DBDelete() Subroutine is called and the selected items will be deleted from the DirectoryList Table and refreshes the ListBox to reflect the change.
The KillTempFile() Subroutine.
Private Sub KillTempFile(ByVal filename As String) On Error GoTo KillTempFile_Err 'Manage Temporary Files If Len(Dir(filename)) > 0 Then Kill filename End If KillTempFile_Exit: Exit Sub KillTempFile_Err: MsgBox Err & ": " & Err.Description, , "KillTempFile()" Resume KillTempFile_Exit End Sub
The Compact/Repair Program creates Temporary Databases for System use and deletes them using the above Subroutine. This Subroutine is called from within the DBPrepare() and DBCompact() Subroutines.
The FLst_ObjInit Interface Class Module VBA Code.
Option Compare Database
Option Explicit
Private cmd As FLst_CmdButton
Private frm As Access.Form
Private Coll As New Collection
'------------------------------------------------------
'Streamlining Form Module Code
'in Stand-alone Class Modules
'------------------------------------------------------
'Database Compact/Repair Utility
'Author: a.p.r. pillai
'Date : 20/02/2024
'Rights: All Rights(c) Reserved by www.msaccesstips.com
'------------------------------------------------------
Public Property Get Ini_Frm() As Access.Form
Set Ini_Frm = frm.m_cFrm
End Property
Public Property Set Ini_Frm(ByRef pFrm As Access.Form)
Set frm = pFrm
Call Class_Init
End Property
Private Sub Class_Init()
On Error GoTo Class_Init_Err
Dim ctl As Control
Dim listcount As Long
Const EP = "[Event Procedure]"
listcount = DCount("*", "DirectoryList")
'If ListBox is empty then disable
'cmdDelete Command Button
If listcount = 0 Then
frm.cmdDelete.Enabled = False
Else
frm.cmdDelete.Enabled = True
End If
For Each ctl In frm.Controls
Select Case TypeName(ctl)
Case "CommandButton"
Select Case ctl.Name
Case "cmdFileDialog", "cmdCompact", _
"cmdDelete", "cmdQuit"
Set cmd = New FLst_CmdButton
Set cmd.cmd_Frm = frm
Set cmd.c_cmd = ctl
cmd.c_cmd.OnClick = EP
Coll.Add cmd
Set cmd = Nothing
End Select
End Select
Next
Class_Init_Exit:
Exit Sub
Class_Init_Err:
MsgBox Err & " : " & Err.Description, , "Class_Init()"
Resume Class_Init_Exit
End Sub
Private Sub Class_Terminate()
Do While Coll.Count > 0
Coll.Remove 1
Loop
End Sub
Within the global declaration area, the FLst_CmdButton Class, the Form Object frm, and the Collection Object Coll are declared. This is succeeded by the inclusion of Get/Set Property Procedures for the frm property. In adherence to common practice, the active Form Object is passed from the Form_Load() Event Procedure into the pFrm parameter, subsequently being assigned to the Form Object frm.
Upon obtaining the reference to the active Form object within the Interface Class, in the subsequent phase of the Set Property Procedure, we invoke the Class_Init() Subroutine.
Within the Class_Init() Subroutine, a constant named "EP" is created to represent the [Event Procedure] text. Following this, a check is implemented to determine the status of the DirectoryList Table, which serves as the source data for the ListBox. If the DirectoryList table is empty, the [Delete from List] Command Button on the Form is disabled.
Within the subsequent For...Next Loop, the program iterates through the Command Buttons on the Form. When a Command Button is identified, an individual instance of the Command Button Wrapper Class is instantiated. This instance is then assigned with the respective Control Reference, and the necessary Events, specifically the Click Events in this case, are enabled. These instances are subsequently stored in the Collection Object, for retaining them in memory.
You may take note of the following Statements:
Set cmd = New FLst_CmdButton
Set cmd.cmd_Frm = frm
Set cmd.c_cmd = ctl
cmd.c_cmd.OnClick = EP
Coll.Add cmd
Set cmd = Nothing
The initial statement initiates the creation of an instance of the FLst_CmdButton Class in memory. Its cmd_frm Property is then configured with the active form object frm, and the current Command Button control Reference in ctl is transmitted to the c_cmd Property. When these two properties are armed with the references of the Form and Command Button, the resulting instance of the Command Button Wrapper Class effectively mirrors the properties and characteristics of the corresponding Command Button on the Form.
The subsequent statement, cmd.c_cmd.OnClick = EP is functionally equivalent to specifying the text [Event Procedure] in the OnClick Event Property of the Command Button. Following the activation of the Event Procedure, the current instance of the Wrapper Class is added to the Collection Object in memory. This enables the capturing of the Event when triggered from the Command Button, subsequently executing the associated Event Procedure in the Wrapper Class Module.
You should not ignore the next statement Set cmd = Nothing.
At this point you may be in doubt when we execute the above statement it will erase the Wrapper Class Instance we created in memory.
- While the resemblance may be apparent, there is a crucial distinction. The inclusion of this instance of the Wrapper Class Object in the Collection Object ensures that the Collection Object remains active, retaining the Wrapper Class Instance in memory until the Form is closed and subsequently cleared.
The reason we need to execute Set cmd = Nothing is to avoid creating the next CmdButton Wrapper Class Instance for another Command Button on the Form without clearing the previous one from memory. Without this step, attempting to create the second instance of the Command Button Wrapper Class could result in overwriting the earlier instance in the same memory location. Thus, resetting cmd ensures that a new instance can be created without interference with the earlier Instance of the Wrapper Class.
If we don't execute the Set cmd = Nothing then only the last Command Button's Event will remain valid and others will keep overwriting the earlier Instances.
- Following the reset of the "cmd" object, the process of creating another instance of the Command Button Wrapper Class involves searching for an available memory area to instantiate a new instance of the Command Button Class. This ensures the proper allocation of memory for the new instance, preventing any potential interference with existing instances.
So, please don't ignore this statement. Since it is a logical issue you may need help finding it so easily when debugging.
The Compact_Repair Form Module VBA Code.
Option Compare Database
Option Explicit
Dim Obj As New FLst_ObjInit
Private Sub Form_Load()
DoCmd.Restore
Set Obj.Ini_Frm = Me
End Sub
Private Sub Form_Unload(Cancel As Integer)
Set Obj = Nothing
End Sub
As customary, we have instantiated the Interface Class FLst_ObjInit in the global declaration section of the Form's Class Module. This declaration ensures that all three sets of Class Modules—Wrapper Class, Interface Class, and Form Class Module—are loaded into memory and poised for operation.
In the Form_Load() event procedure, the obj.Ini_Frm property of the Interface Class is assigned the reference to the active Form object, denoted by Me. This initiates a series of actions, and within moments, the system is primed to handle programmed events and their respective functions.
I hope this utility program proves to be a valuable tool for optimizing your Access applications over an extended period, and the best part is, that it comes at no cost.
The Download Link for Compact/Repair Utility is given below:
- Reusing Form Module VBA Code for New Projects.
- Streamlining Form Module Code - Part Two.
- Streamlining Form Module Code - Part Three
- Streamlining Form Module Code - Part Four
- Streamlining Form Module Code - Part Five
- Streamlining Form Module Code - Part Six
- Streamlining Form Module Code - Part Seven
- Streamlining Form Module Code - Part Eight
- Streamlining Form Module Code - Part Nine
- Streamlining Form Module Code - Part Ten
- Streamlining Form Module Code - Part Elevan
- Streamlining Report Module Code in Class Module
- Streamlining Module Code Report Line Hiding-13.
- Streamlining Form Module Code Part-14.
- Streamlining Custom Made Form Wizard-15.
- Streamlining VBA Custom Made Report Wizard-16.
- Streamlining VBA External Files List in Hyperlinks-17
- Streamlining Events VBA 3D Text Wizard-18
- Streamlining Events VBA RGB Color Wizard-19
- Streamlining Events Numbers to Words-20
- Access Users Group(Europe) Presentation-21
- The Event Firing Mechanism of MS Access-22
- One TextBox and Three Wrapper Class Instances-23
- Streamlining Code Synchronized Floating Popup Form-24
- Streamlining Code Compacting/Repair Database-25
- Streamlining Code Remainder Popup Form-26
- Streamlining Code Editing Data in Zoom-in Control-27
- Streamlining Code Filter By Character and Sort-28
- Table Query Records in Collection Object-29
- Class for All Data Entry Editing Forms-30
- Wrapper Class Module Creation Wizard-31
- wrapper-class-template-wizard-v2
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