i am trying to have variables linked to together like this: (login,pass,name) i want to have several line of those but whenever i register it clears the file help would be appreciated thanks.
Private Sub btn_register_Click(sender As Object, e As EventArgs) Handles btn_register.Click
Dim newline As String
Dim anything As String
password = txt_passwordregister.Text
username = txt_usernameregister.Text
If password <> "" And username <> "" Then
If validatepass() = False Then
MsgBox("please enter more than 8 characters")
Else
newline = txt_usernameregister.Text & "," & txt_passwordregister.Text
If rad_student.Checked Then
anything = newline & "," & txt_fullname.Text
Student.WriteLine(anything)
Student.Close()
Else
End If
MsgBox("You are now registered!")
End If
End If
End Sub
You might want to specify what kind of file you are talking to.
but since you don't actually indicate something in particular, here i used StreamWriter to append lines of text to a file.
Using studentWriter As StreamWriter = New StreamWriter("(<path>\<filename>.<txt>)", True)
studentWriter.WriteLine(anything)
End Using
sorry for my bad english.
You didnt show what's happening with the object Student before..
We assume you are using StreamWriter here??
Our best guess is that you open the file in new file mode rather than append mode..
To enable Append mode, provide the parameter when you create the Student object like this :
Dim Student as New StreamWriter("[File Location]",[Append Mode])
When [Append Mode] is True it will append the file and write after the last line you've written into it before.
When [Append Mode] is False it will treat the file as a new file and all the content inside will be lost.
Related
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
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
I have a program written to be a username/password creator, and there is a section that I am attempting to make that will determine whether the entered username is taken or not, and inform the user. It doesn't seem to be working. My code is as follows:
z = File.OpenText(a)
Do Until z.EndOfStream() = True
Dim password As String
password = CStr(z.ReadLine() & vbCrLf)
If password = TextBox1.Text Then
errors = errors + 1
msgPrompt = msgPrompt & "The username you entered, " & TextBox1.Text & " is already taken."
End If
If errors > 1 Then
TextBox5.Text = errors & " errors occured."
ElseIf errors = 0 Then
TextBox5.Text = "No errors!"
Else
TextBox5.Text = errors & " error occured."
End If
If errors >= 1 Then
Button2.Enabled = True
Else
Button2.Enabled = False
End If
Loop
The passwords are stored line by line in a .txt file, so basically I want the program to go over each entry one by one and see if it matches what the user entered. If I am doing something wrong, please inform me, I'd love to get this script working.
Assuming that the heading of your question is correct, your variables in your code are named incorrectly - This isn't vitally important, but it will confuse whoever comes back in 6 months to maintain the software. Also, when your code is running correctly, as all the usernames will be unique, there is no need to return the number of errors.
It is longer than your original code, but the TextExists function can be used to open the file of your choosing such as the password file and the username file - Though your usernames and password in this situation are better stored in the one file.
'Opens the file and if it contains the input text, returns True. Otherwise returns false
Private Function TextExists(filename As String, inputText As String) As Boolean
Dim z As StreamReader = File.OpenText(filename)
Dim fileText As String
Dim msgPrompt As String = ""
Do Until z.EndOfStream() = True
fileText = CStr(z.ReadLine())
If inputText = fileText Then
Return True
End If
Loop
Return False
End Function
Private Sub CheckUserName()
If TextExists(a, TextBox1.Text) Then
MessageBox.Show("Username Already Exists")
Button2.Enabled = False
Else
Button2.Enabled = True
End If
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
CheckUserName()
End Sub
For serious storage of passwords the username and passwords should be encrypted before they are saved of course, and decrypted when loaded. Saving sensitive information like this in plain text is always a very bad idea.
I need to be able to compare each line of a text file with the text a user has typed in a Text or Combo Box for serial key check and blocking certain website. At the moment, the blocked content is inside the programs code itself.
If ComboBox1.Text = "website.com" Then
WB.DocumentText = My.Settings.BlockedPage
ComboBox1.Text = "Blocked"
Else
WB.Navigate(Me.ComboBox1.Text)
ComboBox1.Items.Add(ComboBox1.Text)
End If
I find this way to be annoying as it would increase the file size of the compiled executable and stop me from updating it without releasing a whole new executable.
I have used this approach in another program, but I am sure the code I have used would compare it to the whole text file and not a line.
Dim key As String
key = My.Computer.FileSystem.ReadAllText("key.txt")
If TextBox1.Text = key Then
'Do functions, such as create licence file
Me.Close()
Else
MsgBox("Incorrect key", MsgBoxStyle.Exclamation, "Key Check")
End If
Would I just be able to modify that code to allow me to do what I want?
Thanks.
Try
If ComboBox1.Text.Equals("website.com") Then
WB.DocumentText = My.Settings.BlockedPage
ComboBox1.Text = "Blocked"
Else
WB.Navigate(Me.ComboBox1.Text)
ComboBox1.Items.Add(ComboBox1.Text)
End If
or
If ComboBox1.Text.Contains("website.com") Then
WB.DocumentText = My.Settings.BlockedPage
ComboBox1.Text = "Blocked"
Else
WB.Navigate(Me.ComboBox1.Text)
ComboBox1.Items.Add(ComboBox1.Text)
End If
use .Equal() or .Contains(). Try using .contain() when your trying to compare with a .txt file
Here is a way of doing that:
Dim lines = System.IO.File.ReadAllLines("File path")
Dim text As String
For i = 0 To lines.Length - 1
text = lines(i).ToString
If text = "Your serial here" Then
MsgBox("Serial found")
else
Msgbox("Serial not found")
End If
Next
This code you can use for the webbrowser:
Dim lines = System.IO.File.ReadAllLines(Application.StartupPath + "file path")
Dim text As String
For i = 0 To lines.Length - 1
text = lines(i).ToString
If WebBrowser1.Url.ToString.Contains(text) Then
WebBrowser1.Navigate("")
End If
Next
The text in the textfile should be in the format of:
www.website.com
It sounds very simple but I have searched and cannot seem to find a way to open a log file which the user just created from my windows form app. The file exits I just want to open it after it is created.
I have a Dim path As String = TextBox1.Text and once the user names and clicks ok on the savefiledialog I have a msgbox that says "Done" and when you hit OK I have tried this
FileOpen(FreeFile, path, OpenMode.Input) but nothing happens. I just want it to open the log and show it to the user so they can edit or save it again or anything.
This is where I got the above code.
http://msdn.microsoft.com/en-us/library/microsoft.visualbasic.filesystem.fileopen.aspx
Searching is difficult because everyone is trying to "Open" a file and process it during runtime. I am just trying to Show a file by Launching it like someone just double clicked it.
Here is the entire Export Button click Sub. It basically writes listbox items to file.
Private Sub btnExport_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnExport.Click
Dim sfd As New SaveFileDialog
Dim path As String = TextBox1.Text
Dim arypath() As String = Split(TextBox1.Text, "\")
Dim pathDate As String
Dim foldername As String
foldername = arypath(arypath.Length - 1)
pathDate = Now.ToString("yyyy-MM-dd") & "_" & Now.ToString("hh;mm")
sfd.FileName = "FileScannerResults " & Chr(39) & foldername & Chr(39) & " " & pathDate
sfd.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Personal)
sfd.Filter = "Text files (*.txt)|*.txt|CSV Files (*.csv)|*.csv"
sfd.ShowDialog()
path = sfd.FileName
Using SW As New IO.StreamWriter(path)
If CkbxFolder.Checked = True Then
SW.WriteLine("Folders")
For Each itm As String In ListBox1.Items
SW.WriteLine(itm)
Next
End If
If CkbxFiles.Checked = True Then
SW.WriteLine("Files")
For Each itm As String In ListBox2.Items
SW.WriteLine(itm)
Next
End If
End Using
MsgBox("Done...")
FileOpen(FreeFile, path, OpenMode.Input) 'Why can't I open a file for you...
End Sub
Do not use the old VB6 methods. They are still here for compatibility reason, the new code should use the more powerful methods in the System.IO namespace.
However, as said in comments, FileOpen don't show anything for you, just opens the file
You coud write
Using sr = new StreamReader(path)
Dim line = sr.ReadLine()
if !string.IsNullOrEmpty(line) Then
textBoxForLog.AppendText(line)
End If
End Using
or simply (if the file is not too big)
Dim myLogText = File.ReadAllText(path)
textBoxForLog.Text = myLogText
As alternative, you could ask the operating system to run the program associated with the file extension and show the file for you
Process.Start(path)
To get the same behavior as if the user double-clicked it, just use System.Diagnostics.Process, and pass the filename to it's Start method:
Process.Start(path)
This will open the file using whatever the default application is for that filename based on its extension, just like Explorer does when you double-click it.