Access vba Check if file exists - vba

I have a database split in FrontEnd and BackEnd.
I have it running:
i) in my office
ii) updating/testing in my personal computer.
My BackEnd file is running in different Folder location according to computer running.
I want to place a code and check if file exist.
Code:
Sub FileExists()
Dim strPath As String '<== Office.
Dim strApplicationFolder As String
Dim strPathAdmin As String '<== Admin.
strPath = "\\iMac\Temp\"
strApplicationFolder = Application.CurrentProject.Path
strPathAdmin = strApplicationFolder & "\Temp\"
If Dir(strApplicationFolder & "SerialKey.txt") = "" Then
'===> Admin User.
If Dir(strPathAdmin & "*.*") = "" Then
'===> Empty Folder.
Else
'===> Files on folder.
End If
Else
'===> Office User.
If Dir(strPath & "*.*") = "" Then
'===> Empty Folder.
Else
'===> Files on folder.
End If
End If
End Sub()
I have this until now.
Any help.
Thank you...

Create a small function to check if a file exists and call it when needed.
Public Function FileExists(ByVal path_ As String) As Boolean
FileExists = (Len(Dir(path_)) > 0)
End Function
Since the backend database paths dont change, why dont you declare two constants and simply check their value?
Sub Exist()
Const workFolder As String = "C:\Work Folder\backend.accdb"
Const personalFolder As String = "D:\Personal Folder\backend.accdb"
If FileExists(workFolder) Then
'Work folder exists
End If
'....
If FileExists(personalFolder) Then
'Personal folder exists
End If
End Sub

This is a very belated reply, but don't reinvent the wheel. VBA can access the FileSystemObject, which includes a powerful set of methods that fetch file and folder information without requiring you to write your own functions, and the resulting code is much easier to read.
Second, borrowing on the previous answer, you know the folders you want the code to look at, and they don't change much, but because they could, I would also move your parameters into the declaration so they can be customized if needed or default to existing values.
Finally, FileExists is a verb, which should scream Function rather than Sub, so I'm guessing you want to return something and use it elsewhere in higher level code. It so happens that FileExists is already the name of a method in FileSystemObject, so I'm going to rename your function to LocatePath. You could return the valid path of the file you're looking for and decide by convention to quietly return an empty string "" if the target isn't found, and handle that in the calling procedure.
fs.BuildPath(strRootPath, strFileOrSubDir) appends strFileOrSubDir to strRootPath to construct a properly
formatted, full pathname and you don't need to worry about
whether you have backslashes (or too many) between the two.
It can be used to append files, or subdirectories, or
files in subdirectories.
fs.FileExists(strFullPath) is simple, returns True if strFullPath exists,
and False otherwise.
fs.GetFolder(strFolderName) returns a Folder object that has a
.Files property, which is a Collection object. Collection
objects in turn have a .Count property, which in this example
indicates how many files are in strFolderName. The Collection
object could also be used to iterate over all the files in the
folder individually.
What follows is your code refactored to incorporate all the changes I recommend according to what I think you're trying to achieve. It's not as symmetric as I'd like, but mirrors your code, and it's simple, easy to read, and finished in the sense that it does something.
Function LocatePath(Optional strWorkPath as String = "\\iMac",
Optional strHomePath as String = CurrentProject.Path,
Optional strFile as String = "SerialKey.txt"
Optional strSubDir as String = "Temp") as String
Dim fs as Object
Set fs = CreateObject("Scripting.FileSystemObject")
If fs.FileExists(fs.BuildPath(strHomePath, strFile)) Then
If fs.GetFolder(fs.BuildPath(strHomePath, strSubDir).Files.Count > 0 Then '===> Admin User.
LocatePath = fs.BuildPath(strHomePath, strFile)
ElseIf fs.GetFolder(fs.BuildPath(strWorkPath, strSubDir).Files.Count > 0 Then '===> Office User
LocatePath = fs.BuildPath(strWorkPath, strFile)
End If
Else 'Target conditions not found
LocatePath = ""
End If
Set fs = Nothing
End Function()
Ideally, I probably wouldn't specify strHomePath as String = CurrentProject.Path because strWorkPath as String = CurrentProject.Path is probably also true when you're at work, and you would want to do a better job of differentiating between the two environments. This is also what causes the little problem with symmetry that I mentioned.

Related

Add a path to a code VB.net / visual basic

how do I add a path to a code where "HERE_HAS_TO_BE_A_PATH" is. When I do, Im getting an error message. The goal is to be able to specific the path where is the final text file saved.
Thanks!
Here is a code:
Dim newFile As IO.StreamWriter = IO.File.CreateText("HERE_HAS_TO_BE_A_PATH")
Dim fix As String
fix = My.Computer.FileSystem.ReadAllText("C:\test.txt")
fix = Replace(fix, ",", ".")
My.Computer.FileSystem.WriteAllText("C:\test.txt", fix, False)
Dim query = From data In IO.File.ReadAllLines("C:\test.txt")
Let name As String = data.Split(" ")(0)
Let x As Decimal = data.Split(" ")(1)
Let y As Decimal = data.Split(" ")(2)
Let z As Decimal = data.Split(" ")(3)
Select name & " " & x & "," & y & "," & z
For i As Integer = 0 To query.Count - 1
newFile.WriteLine(query(i))
Next
newFile.Close()
1) Use a literal string:
The easiest way is replacing "HERE_HAS_TO_BE_A_PATH" with the literal path to desired output target, so overwriting it with "C:\output.txt":
Dim newFile As IO.StreamWriter = IO.File.CreateText("C:\output.txt")
2) Check permissions and read/write file references are correct:
There's a few reasons why you might be having difficulties, if you're trying to read and write into the root C:\ directory you might be having permissions issues.
Also, go line by line to make sure that the input and output files are correct every time you are using one or the other.
3) Make sure the implicit path is correct for non-fully qualified paths:
Next, when you test run the program, it's not actually in the same folder as the project folder, in case you're using a relative path, it's in a subfolder "\bin\debug", so for a project named [ProjectName], it compiles into this folder by default:
C:\path\to\[ProjectName]\bin\Debug\Program.exe
In other words, if you are trying to type in a path name as a string to save the file to and you don't specify the full path name starting from the C:\ drive, like "output.txt" instead of "C:\output.txt", it's saving it here:
C:\path\to\[ProjectName]\bin\Debug\output.txt
To find out exactly what paths it's defaulting to, in .Net Framework you can check against these:
Application.ExecutablePath
Application.StartupPath
4) Get user input via SaveFileDialogue
In addition to a literal string ("C:\output.txt") if you want the user to provide input, since it looks like you're using .Net Framework (as opposed to .Net Core, etc.), the easiest way to set a file name to use in your program is using the built-in SaveFileDialogue object in System.Windows.Forms (like you see whenever you try to save a file with most programs), you can do so really quickly like so:
Dim SFD As New SaveFileDialog
SFD.Filter = "Text Files|*.txt"
SFD.ShowDialog()
' For reuse, storing file path to string
Dim myFilePath As String = SFD.FileName
Dim newFile As IO.StreamWriter = IO.File.CreateText(myFilePath) ' path var
' Do the rest of your code here
newFile.Close()
5) Get user input via console
In case you ever want to get a path in .Net Core, i.e. with a console, the Main process by default accepts a String array called args(), here's a different version that lets the user add a path as the first parameter when running the program, or if one is not provided it asks the user for input:
Console.WriteLine("Hello World!")
Dim myFilePath = ""
If args.Length > 0 Then
myFilePath = args(0)
End If
If myFilePath = "" Then
Console.WriteLine("No file name provided, please input file name:")
While (myFilePath = "")
Console.Write("File and Path: ")
myFilePath = Console.ReadLine()
End While
End If
Dim newFile As IO.StreamWriter = IO.File.CreateText(myFilePath) ' path var
' Do the rest of your code here
newFile.Close()
6) Best practices: Close & Dispose vs. Using Blocks
In order to keep the code as similar to yours as possible, I tried to change only the pieces that needed changing. Vikyath Rao and Mary respectively pointed out a simplified way to declare it as well as a common best practice.
For more information, check out these helpful explanations:
Can any one explain why StreamWriter is an Unmanaged Resource. and
Should I call Close() or Dispose() for stream objects?
In summary, although streams are managed and should garbage collect automatically, due to working with the file system unmanaged resources get involved, which is the primary reason why it's a good idea to manually dispose of the object. Your ".close()" does this. Overrides for both the StreamReader and StreamWriter classes call the ".dispose()" method, however it is still common practice to use a Using .. End Using block to avoid "running with scissors" as Enigmativity puts it in his post, in other words it makes sure that you don't go off somewhere else in the program and forget to dispose of the open filestream.
Within your program, you could simply replace the "Dim newFile As IO.StreamWriter = IO.File.CreateText("C:\output.txt")" and "newFile.close()" lines with the opening and closing statements for the Using block while using the simplified syntax, like so:
'Dim newFile As IO.StreamWriter = IO.File.CreateText(myFilePath) ' old
Using newFile As New IO.StreamWriter(myFilePath) ' new
Dim fix As String = "Text from somewhere!"
newFile.WriteLine(fix)
' other similar operations here
End Using ' new -- ensures disposal
'newFile.Close() ' old
You can write that in this way. The stream writer automatically creates the file.
Dim newFile As New StreamWriter(HERE_HAS_TO_BE_A_PATH)
PS: I cannot mention all these in the comment section as I have reputations less than 50, so I wrote my answer. Please feel free to tell me if its wrong
regards,
vikyath

Delete items within a folder rather than deleing the entire folder itself using vb.net

I want to delete all the files contained in a folder. The below code does delete the file but also deletes the folder itself. I am aware you will need to perform a for loop to remove each item from the folder, but can't find the information on how to start the code for it. Can someone point me in the correct direction.
Dim folderFiles() As String
folderFiles= Directory.GetFileSystemEntries("C:\New Folder")
For Each element As String In files
If (Not Directory.Exists(folder)) Then
File.Delete(Path.Combine("C:\New Folder", Path.GetFileName(folder)))
End If
Next
This is the easier way :
For Each the_file As String In Directory.GetFileSystemEntries("C:\New folder")
File.Delete(the_file)
Next
Don't bother to grab the list of files and then browse it, use your loop directly on it.
I have a function for that. With it, you can also delete all files of a pattern even for all subdirectories:
Public Sub DeleteFiles(Path As String,
Optional Pattern As String = "*.*",
Optional All As Boolean = False)
Dim SO As IO.SearchOption = If(All, IO.SearchOption.AllDirectories, IO.SearchOption.TopDirectoryOnly)
For Each Filename As String In Directory.GetFiles(Path, Pattern, SO)
File.Delete(Filename)
Next
End Sub
So you could use it for your task like:
DeleteFiles("C:\New Folder")
I would use this code
For Each file As String In IO.Directory.GetFiles("the path")
IO.File.Delete(file)
Next
This deletes everything in the folder but not the folder itself.
This is quick and easy, especially if 1) there's nothing special about the folder, eg permissions, and 2) the folder might contain sub-folders, sub-sub-folders, etc.
Simply delete the original folder and recreate it:
Dim path As String = {your path}
IO.Directory.Delete(path, recursive:=True)
IO.Directory.CreateDirectory(path)
Another option for folders with sub-folders where you wish to keep the (empty) sub-folders, is to use recursion:
Sub EmptyFolder(path As String) As Boolean
Try
For Each dir As String In IO.Directory.GetDirectories(path)
EmptyFolder(dir)
Next dir
For Each file As String In IO.Directory.GetFiles(path)
IO.File.Delete(file)
Next file
Catch
Throw
End Try
End Function

Moving Files From One Folder To Another VB.Net

I am trying to figure out how to move 5 files
settings.txt
settings2.txt
settings3.txt
settings4.txt
settings5.txt
from one folder to another.
Although I know what the file names will be and what folder Name they will be in, I don't know where that folder will be on the Users computer.
My thought process is to use a FolderBrowseDialog which the user can browse to where the Folder is, and then when OK is pressed, it will perform the File copy to the destination folder, overwriting what's there.
This is what I have so far.
Dim FolderPath As String
Dim result As Windows.Forms.DialogResult = FolderBrowserImport.ShowDialog()
If result = DialogResult.OK Then
FolderPath = FolderBrowserImport.SelectedPath & "\"
My.Computer.FileSystem.CopyFile(
FolderPath & "settings.txt", "c:\test\settings.txt", overwrite:=True)
ElseIf result = DialogResult.Cancel Then
Exit Sub
End If
Rather than run this 5 times, is there a way where it can copy all 5 files at once
I know why IdleMind recommended the approach they did, but it would probably make for a bit more readable code to just list out the file names:
Imports System.IO
...
Dim result = FolderBrowserImport.ShowDialog()
If result <> DialogResult.OK Then Exit Sub
For Each s as String in {"settings.txt", "settings2.txt", "settings3.txt", "settings4.txt", "settings5.txt" }
File.Copy( _
Path.Combine(FolderBrowserImport.SelectedPath, s), _
Path.Combine("c:\test", s), _
True _
)
Next s
You can swap this fixed array out for a list that VB prepares for you:
For Each s as String in Directory.GetFiles(FolderBrowserImport.SelectedPath, "settings*.txt", SearchOption.TopDirectoryOnly)
File.Copy(s, Path.Combine("c:\test", Path.GetFilename(s)), True)
Next s
Tips:
It's usually cleaner to do a If bad Then Exit Sub than a If good Then (big load of indented code) End If - test all your known failure conditions at the start and exit the sub if anything fails, rather than arranging a huge amount of indented code
Use Path.Combine to combine path and filenames etc; it knows how to deal with stray \ characters
Use Imports to import namespaces rather than spelling everything out all the time (System.Windows.Forms.DialogResult - a winforms app will probably have all the necessaries imported already in the partial class so you can just say DialogResult. If you get a red wiggly line, point to the adjacent lightbulb and choose to import System.WIndows/Forms etc)
Once you have the selected folder, use a For loop to build up the names of the files you're looking for. Use System.IO.File.Exists() to see if they are there. Use System.IO.Path.Combine() to properly combine your folders with the filenames.
Here's a full example (without exception handling, which should be added):
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
If FolderBrowserImport.ShowDialog() = DialogResult.OK Then
Dim FolderPath As String = FolderBrowserImport.SelectedPath
For i As Integer = 1 To 5
Dim FileName As String = "settings" & If(i = 1, "", i) & ".txt"
Dim FullPathFileName As String = System.IO.Path.Combine(FolderPath, FileName)
If System.IO.File.Exists(FullPathFileName) Then
Dim DestinationFullPathFileName = System.IO.Path.Combine("c:\test", FileName)
My.Computer.FileSystem.CopyFile(FullPathFileName, DestinationFullPathFileName, True)
Else
' possibly do something in here if the file does not exist?
MessageBox.Show("File not found: " & FullPathFileName)
End If
Next
End If
End Sub

Copy file with progress bar bypass file replacement confirmation

This is a follow up to this question and great answer:
Copy files with progress bar
So I added the code from Siddharth Rout's answer and it does exactly what I want to happen with a minor exception. When I copy the files, I am looping through each file in the directory and copying it up as long as it is not *List.xml. Because I am replacing an existing library the 97% of the documents are pre-existing and I get prompted to replace existing documents each time.
Is there a way to get it to prompt me to choose to replace for all files? Do I need to reformat/structure the sequence of my code?
Function UploadToSharepoint(Folderpath As String, Foldername As String, Filenames() As String, SharepointLinks() As String) As Boolean
'upload file to sharepoint library based on the folder name
Dim SharePointLib As String
Dim LocalAddress As String
Dim DestinationAddress As String
Dim xCounter As Long
On Error GoTo loadFailed
Pickafolder:
Folderpath = FolderPick
Foldername = Left(Folderpath, Len(Folderpath) - 1)
Foldername = RIght(Foldername, Len(Foldername) - InStrRev(Foldername, "\"))
Select Case Foldername
Case "OPSS", "SSP", "OPSD", "MTOD", "SSD"
SharePointLib = "\\my.company.com\Subsite\" & Foldername & "\"
Case "West", "Eastern", "Northeastern", "Northwestern", "Head Office"
SharePointLib = "\\my.company.com\Subsite\NSP\" & Foldername & "\"
Case "NSP", "NSSP"
MsgBox "Pick the NSP regional sub folder: West, Eastern, Northeastern, Northwestern, Head Office"
GoTo Pickafolder
Case Else
MsgBox "Inappropriate directory to upload from. Please select one of the CPS download directories"
GoTo Pickafolder
End Select
Filenames = GetFilesDir(Folderpath)
ReDim SharepointLinks(LBound(Filenames) To UBound(Filenames))
For xCounter = LBound(Filenames) To UBound(Filenames)
LocalAddress = Folderpath & Filenames(xCounter)
DestinationAddress = SharePointLib & Filenames(xCounter)
'**********************************************************
Call VBCopyFolder(LocalAddress, DestinationAddress)
'**********************************************************
SharepointLinks(xCounter) = "#http:" & Replace(DestinationAddress, "\", "/") & "#"
Next xCounter
UploadToSharepoint = True
Exit Function
loadFailed:
UploadToSharepoint = False
End Function
And by the looks of things I am not excluding the file I was referring to earlier...must be doing that else where.
Update
Based on comment received at the linked question, the solution is to declare a public constant at the start:
Public Const FOF_NOCONFIRMATION As Long = &H10
and then in the copy procedure change the line of code to:
.fFlags = FOF_SIMPLEPROGRESS Or FOF_NOCONFIRMATION
Now, this does solve the problem of being constantly asked to confirm the replacement. I am very happy about this. The problem now is the progress window displays for the first file to be copied then disappears but fails to reappear for subsequent files. The remaining files still get copied and the prg carries on like it's supposed to. The whole point of the progress bar though was to let people know that "THINGS" were still happening in the background and now that is not happening. Is there something I need to adjust?
Update 2
After running my code and choosing a source directory on the network drive instead of the local computer, the copy window is popping up for every single file like I was expecting. I notice that sometimes the progress bar closes before reaching 100%. This leads me to believe that since the file sizes are so small that when it is copying from my local drive to sharepoint, the operation completes so fast that it does not have time to draw and update the progress window before its time to close it.

Delete A File That Contains The App Name (VB.NET)

This is the code I'm Using:
Dim file As String
Dim prefetchPath As String
Dim FileName As String = My.Application.Info.AssemblyName
prefetchPath = Environment.GetEnvironmentVariable("windir", EnvironmentVariableTarget.Machine) & "\Prefetch"
For Each file In IO.Directory.GetFiles(prefetchPath)
If file.Contains(FileName) Then
IO.File.Delete(file)
End If
Next
i don't know why it does not work if i use FileName. But it work if i use this code
If file.Contains("Example.exe") Then
IO.File.Delete(file)
End If
I want to make sure that if someone changes the name of the application the code works the same way(I already running the file as Administrator)
Help me Thanks.
My guess is that AssemblyName only returns the name without the extension, try including the .exe. Also, it is worth noting that you can use the IO.DirectoryInfo class and pass the file name in the GetFiles method to cut out your For/Each loop.
Here is a quick example:
Dim prefetchPath As String = IO.Path.Combine(Environment.GetEnvironmentVariable("windir", EnvironmentVariableTarget.Machine), "Prefetch")
Dim FileName As String = My.Application.Info.AssemblyName & ".exe"
If New IO.DirectoryInfo(prefetchPath).GetFiles(FileName).Count > 0 Then
IO.File.Delete(IO.Path.Combine(prefetchPath, FileName))
End If