Handling Unauthorized-access Exceptions When Searching Folders
May 18, 2010
If any directory within a set being searched by the [URL] or [URL] methods contains a junction point, the entire method fails and returns zero results on my tests under VB 2008. I would like to make the call more robust: to return the folders or files not blocked by access restrictions and to note the folders which were blocked. Do those methods offer a means to do this, or is a recursive folder-by-folder call necessary?
My current project is to search the computer for exe files, I managed to do that easily with a for...each statement. It ran well, but it came to a adminstrator folder, then it said "Access Denied".I understand that you cant access these folders, but i was wondering how to exclude certain directories that the user can't access, like UAC or something.[code]
All of us use the try catch blocks. But what is the best way of handling errors within custom functions?Display a messagebox to the user when the exception is thrown (if possible within the function), or return a value indicating that an error was found within the function?
I have set up a process to create new tasks to handle file processing. A problem arised where I received and unhandled exception error and just clicking on the continue button, the main process continued to run. Now I also found that within the child task I was having a file conflict error and as the tasks run as separate .exe i was under the impression that everything would have been thread safe. So for the first issue here is the task creation in the main process..GProcess is a complete project on its own consisting of 6 classes. This is added as a class library reference to the main process class form1
Public Class Form1 ..Private parser as GProcess.module = new GProcess.module() dim factory as new taskfactory
This was a difficult question to google. I have an Order class with a couple of dozen properties such as ClientReference, ShipMethod, etc. I use databinding to bind this class to an Order form. If a user enters an invalid shipping method, an exception is raised in the ShipMethod property and a validation error is displayed to the user. But I'm trying to use the same Order class within an OrderImport class whose job it is to take a flat file and create multiple orders. The problem occurs if I'm assigning to a dozen of the order fields consecutively, and say the first one causes a validation exception. If I have all dozen assignments occuring within a single try-catch block, the next 11 assignments will be skipped and I'll only be able to record one validation error. I could solve the problem by doing a dozen separate try-catch statements, but that doesn't seem very elegant.
What are some of the most common mistakes you've seen made when handling exceptions?It seems like exception handling can be one of the hardest things to learn how to do "right" in .Net. Especially considering the currently #1 ranked answer to Common programming mistakes for .NET developers to avoid? is related to exception handling.
When two computers are connected through TCP, and one of them closes and breaks the connection, it throws error 10054 "Remote host forcibly closed the connection".I want to handle this error because I know it will happen more often than not with the application I'm building. In System.Net.Sockets.SocketException, there is an on the error code. But when I run the program, the exception that is being thrown is System.IO.IOException, and the GetType for IOException is the socket exception. I don't know how to handle the socket exception if it's not the root cause of the exception.
Here is the code for my Try Catch block: For infiniteCounter = 1 To 2 infiniteCounter = 1
So I've made this control that inherits from the treeview control and basically loads objects from active directory into a treeview (url...).All working fine, but as this is the first custom control I have made that I have intended for other people to use, I'm not quite sure how I should approach error handling.I mean, obviously I shouldnt do something like show any exceptions in a messagebox because that might not be what the person that is using the control wants to happen. So do I just write out exception messages to the debug window? Do I swallow exceptions (guessing not)? Do I just totally ignore them so that they are thrown in the user's project?
i created a Class library (.dll) and loaded it as reference into a main project. In the code for the class i've handled exceptions using try..catch subs, however when debugging the main project exceptions that are handled in the DLL still get thrown! (the class ".vb" file gets loaded into the debugger and the line of the exception shows up)
Up till now i've found it useful that when an unhandled error occurs in the imported reference, it shows up in the main project with tracing back to the referenced class. But i dont want the exceptions that are handled in the reference class to be thrown when debugging the main project!
As you can see the exception thrown was handled with try...catch this class exception.vb belongs to the project that created the class library (.DLL that i referenced). i didnt even load the project that built the reference so it amazes me that it could find the coding class to begin with.
I am writing a class library that envelopes an USB device driver. This device has its own class library, provided by the hardware vendor.
Very often, especially if you handle with old DLL or COM assemblies, there are methods (functions to be correct) that return TRUE if all was OK, or FALSE if any error happen. Often these methods return information about the error in one of their parameters or separately in a GetLastError method or even if in an OnError event.
Now, normally I handle all native .NET exceptions in my class libray handling locally or re-throwing to the client if the error is useful to know. But what to do with all other errors that are hidden in the vendor's methods? (in the true I have no exceptions, but only returned TRUE or FALSE values).
Let's make an example with the method "CONNECT" that connect the client to the USB device.
I envelope the method in this way:
Public Sub Connect() oVendorDevice.connect() End Sub
now if any connection error happen, the vendor's connect method return FALSE. But I do not know why the connection failed. To know why the connection failed I have to call (for example) the method GetLastError that gives me information about the error. (but do not forget that other vendors use other strategies like returning the error in a method's parameter or in a OnError events.
Now, in order to follow a good .NET exception handling strategy I could write something like this:
Public Sub Connect() Dim res As Boolean = oVendorDevice.connect() If res = False Then
I had an exercise where I was supposed to have a button open an openfile dialog box, let the user select a file, then another button that would save the file with the extension ".bak". The author didn't give any clues about manipulating extensions -- but a few chapters back we covered string functions. So, with that in mind, I did the following...
Private Sub btnSaveFile_Click(sender As System.Object, e As System.EventArgs) Handles btnSaveFile.Click ' Where does the extension start
i have a folder that contains folders that contain fileslets say i have a folder named schoolin this folder there are other folders for each subject: math folder - physics folder - chemistry folder ....... and so onin each folder, lets say the math folder contains many files for previous quizes and exams, like : midterm2007.pdf - midterm2008.pdf - final2008.doc - final2008.docxnow what i want to do, is a tool that searches the school directory and gets for me all " files " this is what
Ive created a simple application that works fine when i debug and test it though visual studio but when i deploy the application, download it and install it onto my machine i get an error.basically when the first form loads it checks for a file called "New Folder" in my program files folder on my machine if the file is not there, then it adds the file. the code im using to do this is:
If System.IO.Directory.Exists(My.Computer.FileSystem.SpecialDirectories.ProgramFiles & "New Folder") Then Exit Sub()
so i will try and make this simple, im writing a program in VB 2008 and i need to search through the whole hard drive for a specific file type, in my case they are .psd files so im using this line of code:
I am just writing a simple file browser. It works without problems when I point to a specific directory but throws "UnauthorizedAccessException access to the path .... is denied" when I point to drive "C:\" or "D:\".
If Not txtToSearch.Text = Nothing Then ListBox1.Items.Clear() FC = 0 For Each foundfile As String In My.Computer.FileSystem.GetFiles("D:\", FileIO.SearchOption.SearchAllSubDirectories, Nothing) Dim title As String = My.Computer.FileSystem.GetFileInfo(foundfile).Name If title.Contains(txtToSearch.Text) Then ListBox1.Items.Add(title) FC += 1 End If Next
I am trying to get a list of files using this line of Dim files() As String = IO.Directory.GetFiles("D:", "*.*", SearchOption.AllDirectories)But it errors out on folders that are inaccessible, like the RecycleBin folder & the program stops. So how do I get a list of files in all folders, while skipping the inaccessible one
I am creating a file and then trying to read and write to it. I'm coming up with an UnauthorizedAccessException wa unhandled. My question is, How do I get around this properly or otherwise improperly to read and write to my text file?
Imports Scripting Imports System.IO Imports System.Security Imports System.Security.Permissions Public Class Form1 [Code] .....
I'm trying to write a console application that can modify registry subkeys on remote pc's in the same network. I have it working in my own environment but when I install on the customer machines I'm getting unauthorized access when it hits the OpenRemoteBaseKey. The security settings in the application properties is set to full trust application so I'm not sure why it won't work.
I'm using Visual Studio 2010 and first I just installed it on the customer machine and when it wouldn't work I ran the source code in Visual Studio 2005 which is on the customer machine but got same results.I can run the app directly on the remote machine and it will change the registry subkeys as directed, I just can't do it remotely. RemoteRegistry service is started. Both machines are logged in as administrators.
Here is the source code:
Imports Microsoft.VisualBasic Imports System Imports System.IO Imports System.Security.Permissions
I'm running Windows Vista with admin privilege and UAC is disabled but still unable to write to windows registry! My.Computer.Registry.SetValue _ ("HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRun", _ "Test", "C:Test.exe", Microsoft.Win32.RegistryValueKind.String)
I'm getting error "Unauthorized Access Exception was unhandled." "Access to the registry key 'HKEY_LOCAL_MACHINE....' is denied."
I've googled the net and found that registry permission elevation is required for admin tasks, Is there away to take registry key ownership through VB.Net code??
My application creates a file by writing to System.AppDomain.CurrentDomain.BaseDirectory() & "data/" & filename...Now this works fine usually, but I just added a setup utility to the app, so now it installs to the program files directory. It installs correctly and creates the data folder, however when it tries to write the file it gets an exception "unauthorized access".
I'm developing an application to help law enforcement retrieve and analyze logs and other files left by the use of Pidgin (a multi-protocol messenger client). Right now I'm nearly done, but I want to add the ability to search chat logs for user-defined words or phrases and I don't even know where to begin.
Chat logs are stored as html documents in a folder/sub-folder/sub-folder/sub-folder fashion, where each sub-folder can have dozens of sub-folders inside of it, and the final sub-folder can have dozens if not hundreds of chat logs. If anybody could point me in the right direction, I'd be very grateful.
(Also, this is the first program I've written since about 2005, and I'm essentially teaching myself VB as I go. If you'd like to see what I've cobbled together so far, you can find the program here.)
I've just skipped around a few inbuilt VB classes' methods which throws exception. of all that i've came across, methods may throw multiple exceptions but ALL of them are exclusive, meaning there is no way 2 exceptions will ever occur simultaneously, yea and i was trying to make my class throw 2 exceptions simultaneously, hence this question, must all exceptions be exclusive?
at I do not know the number of or the names of the folders, they can be different in different cases, I only have the root path.how I can display folder contents in VB.net and the code worked but couldn't figure out how to create the arrays and display only folders within folders starting with "ad_".
I want to specify which folders the treeview can access or not access(which ever is easiest).The following what I have:
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Dim getInfo As System.IO.DriveInfo() getInfo = System.IO.DriveInfo.GetDrives Dim newNode As TreeNode
I tried looking up Threads that would search through an access database, but I keep running into this:
502 Bad Gateway
The server returned an invalid or incomplete response.Is there any threads that would help me? For example, in my program if I wanted to search for a certain customer I would enter their info in text box and it would search through my Access database. I have all ready added the data source and even added a section where they could add in somebody to the database. But I can't seem to get the search part down?
my search function is functional however, it does not behave as what i intended it to be. I have a Text box call Text1 and I have a button called cmdSearch. when i click the cmdSearch, the text in Text will search it in my MS access file here is my code:
Code: Private Sub cmdSearch_Click() RS.Open "SELECT * FROM productTB where Pname like '%" & Text1 & "%'", Con
I haven't programmed in over a year and I am trying to get this to work. I have a sample database containing 4 columns (First_Name, Last_Name, Emp_Num, and Image). I wanting to type my search criteria in a textbox and search the access database by first and last names. nce the record is found I am wanting to display the name and image for that person. I have already linked my database to my project
I have a very simple VB.net Windows Service written using VS.net 2008. The program after doing several other functions writes a log in one of the network folders. The code is as shown below: If I change the path from "Y:Activity_Log" to "C:Activity_Log" it is working like a charm.What is the problem if I use Y drive which is a valid one and I am able to access it from other VB.net desktop apps. Please help.
Dim strFile As String = "Y:Activity_Log" & DateTime.Today.ToString("dd-MMM-yyyy") & ".txt" Dim fs As FileStream = Nothing Dim activityfolder As String = "Y:Activity_Log" Dim di As System.IO.DirectoryInfo
I know how to search for one specific number from a single line in an access database using a query, but now I have to search through a whole database and display each instance. Ex) I search the number "1" in column "1" of the database and it has "2" instances. So now I have to take the corresponding data in the rows next to it in order to display them in the label.
Am working on a movie rental system in VB.NET, but there's a problem. I want a situation whereby the user will have the privilege to search for desired records by typing a search string, then hitting the search button. The results should be shown on a datagridview. Here's my code:
Private Sub btnSearch_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSearch.Click Dim MovieName As String
Im new to db access and Im not quite familiar to searching. How can I search all my field and will show the nearest match for the keyword and will be shown under the combobox the nearest results that it can find in my db. Like searching search engines like Google that you can find their suggestions under the combobox ?
I'm fiddling around with a small program that can delete a directory, including its sub-folders and files.This is the code I'm using: (Note-I found it on the net, I didn't code it myself)
Private Sub filedelete(ByVal filename As String) Dim filesystemobject As Object filesystemobject = CreateObject("Scripting.filesystemobject")[code]..........
So on click of button '2' the folders are cleaned out, and on click of button '3' they are deleted - it works great.Now the problem is, if any of the folders in the directory 'test' are not accessible to the current user, the program throws the exception 'Access to the path is denied.Is it possible to skip folders that are not accessible, and just ignore them, and delete the ones that are accessible?What code needs to be added to enable this ability?
Here is my vb.net Module FileCheck Public BW_AntiCorrupt As New Threading.Thread(AddressOf AntiCorrupt) Dim THardDrive As String = Environment.GetFolderPath(Environment.SpecialFolder.Desktop) Dim HardDrive As String = THardDrive.Substring(0, THardDrive.IndexOf("") + 1) 'C: Public ContinueSearch As Boolean = True [Code] .....
I am having a problem. The IO.Directory.GetFiles code is resulting in error do to the fact that it is trying to access the Temp folder in the Windows folder on drive C:. Apparently that folder is restricted... When the code encounters that folder the code stops retrieving files. Is there a way around this? Is there somewhere i can give my program administrator access? If not then am i able to skip the files in that location?