I am trying to create an onclick function through ASP front end to check if a file exists, if not create it and write textbox text to it, currently getting an error on the below code saying that I cannot overload the file function, is there a better way of doing this?
UPDATE
The issue is the file is still open when trying to write to it which is throwing the error.
Please see below code:
Protected Sub Create_Click(sender As Object, e As EventArgs)
Dim txtFile As String = "E:Documents\Visual Studio 2013\Projects\SomeProject\Templates\" & FileName.Text & ".txt"
If File.Exists(txtFile) Then
Response.Write("A file of that name already exists.")
Else
File.Create(txtFile)
File.WriteAllText(eTemplate.Text)
End If
End Sub
I have also tried:
If File.Exists(txtFile) Then
Response.Write("A file of that name already exists.")
Else
System.IO.File.Create(txtFile)
Dim sw As New StreamWriter(txtFile, True)
sw.Write(eTemplate.Text)
sw.Close()
End If
You're right on the money, it is because it needs to be closed first.
I created a file stream instance first, created the file, closed it and then wrote to it. Put the below code in yours or write it out, but remember to correct the file path.
Protected Sub Create_Click(sender As Object, e As EventArgs)
Dim txtFile As String = "E:\wherever\" & FileName.Text & ".txt"
If System.IO.File.Exists(txtFile) Then
Dim message As String = "A file by this name already exists, choose another or update the existing file."
Else
Dim fs As FileStream = File.Create(txtFile)
fs.Close()
Dim sw As New StreamWriter(txtFile, True)
sw.Write(eTemplate.Text)
sw.Close()
End If
End Sub
Related
i been given a assignment to create one console application using VB.NET. The assignment will able to open the file that based on the date modified entered by user. can anyone help me to solve my problem. I'm new in vb.net and most of the tutorial are using C# . together i put the latest code i has already done but still if i put the date modified the error file will display .
Thank you in advance
Imports System.IO
Module Module3
Sub Main()
While True
' Read value.
Dim s As DateTime = Console.ReadLine()
' Test the value.
If s = File.GetLastWriteTime("path") Then
Dim p As New Process()
p.StartInfo = New ProcessStartInfo("notepad.exe", "path")
p.Start()
Else
Dim p As New Process()
p.StartInfo = New ProcessStartInfo("notepad.exe", "path2")
p.Start()
End If
' Write the value.
Console.WriteLine("You typed " + s)
End While
End Sub
End Module
in the code snippet you are not searching for a file you are setting the time last modified which isn't what you want to do.
you will need to search through each file until you find the date modified information which is inputted by the user:-
dim s as datetime = console.readline()
'Target Directory
Dim directory = "C:\Users\Peter\Desktop\TestFolder\"
For Each filename As String In IO.Directory.GetFiles(directory, "*", IO.SearchOption.AllDirectories)
Dim fName As String = IO.Path.GetExtension(filename)
dim datemod as string = File.GetLastWriteTime(directory & fname)
If s = datemod Then
Dim p As New Process()
p.StartInfo = New ProcessStartInfo("notepad.exe", directory & fname)
p.Start()
Else
'do something else
endif
next
things that you will need to add are, what to do when it doesn't find a file with that variable.
hope this gets you a little further.
I'm trying to figure out a problem that we're facing with the download and the problem seems to exist only in Chrome and only for txt and csv files. Downloading zip files works just as expected. IE and Firefox works for all scenarios.
For some reason Chrome downloads both txt and csv files without properly setting the name. Files inherit the name of the page which they were downloaded from, and don't have an extension ().
I have a simple Webform with just 3 linkbuttons a fairly straightforward code behind, which I simplified for the sake of this question.
Imports System.IO
Public Class _Default
Inherits Page
Private Const FILE_PATH_CSV As String = "D:\Temp\Download\testFile.csv"
Private Const FILE_PATH_ZIP As String = "D:\Temp\Download\testFile.zip"
Private Const FILE_PATH_TXT As String = "D:\Temp\Download\testFile.txt"
Private Sub btnDownloadCSV_Click(sender As Object, e As EventArgs) Handles btnDownloadCSV.Click
Dim file As New FileInfo(FILE_PATH_CSV)
If Not file.Exists() Then
Throw New Exception("No file")
End If
Try
DownloadFile(file)
Catch ex As Exception
'TODO: Log!
End Try
End Sub
Private Sub btnDownloadTXT_Click(sender As Object, e As EventArgs) Handles btnDownloadTXT.Click
Dim file As New FileInfo(FILE_PATH_TXT)
If Not file.Exists() Then
Throw New Exception("No file")
End If
Try
DownloadFile(file)
Catch ex As Exception
'TODO: Log!
End Try
End Sub
Private Sub btnDownloadZIP_Click(sender As Object, e As EventArgs) Handles btnDownloadZIP.Click
Dim file As New FileInfo(FILE_PATH_ZIP)
If Not file.Exists() Then
Throw New Exception("No file")
End If
Try
DownloadFile(file)
Catch ex As Exception
'TODO: Log!
Finally
With Response
.Flush()
.End()
End With
End Try
End Sub
Private Sub DownloadFile(ByVal file As FileInfo)
With Response
.Clear()
.ClearHeaders()
.ClearContent()
.Buffer = True
Response.ContentType = GetContentType(file)
Response.AddHeader("Content-Disposition:", String.Format("attachment;filename=""{0}""", file.Name.ToString()))
Response.AddHeader("Content-Length", file.Length.ToString())
Response.TransmitFile(file.FullName)
End With
End Sub
Private Function GetContentType(ByVal file As FileInfo)
Select Case file.Extension.ToLower()
Case ".txt", ".csv"
Return "application/octet-stream"
Case ".zip"
Return "application/x-zip-compressed"
Case Else
Return "application/octet-stream"
End Select
End Function
End Class
I've tried switching the content type to 'text/plain' or other options as I searched the web for the answer but had no luck. I feel like I'm missing something, but I can't find anything that answers my question online.
Does anyone have any ideas why this might be happening?
Any help is appreciated.
You need to change your MIME types to the correct values.
Case ".csv"
Return "text/csv"
Case ".txt"
Return "text/plain"
You may also need to change the method of sending the file from
Response.TransmitFile(file.FullName)
to
Response.WriteFile(file.FullName, False)
The documentation on MSDN isn't clear about what the differences are between the two methods. I have never used TransmitFile, but have used WriteFile successfully.
Problem solved. I guess I should be more careful with copy/paste as that caused me 2 days of very frustrated debugging.
Response.AddHeader("Content-Disposition:", String.Format("attachment;filename=""{0}""", file.Name.ToString()))
Should be
Response.AddHeader("Content-Disposition", String.Format("attachment;filename=""{0}""", file.Name.ToString()))
Extra colon in there was not necessary and when I removed it - everything worked!
Thanks to all who helped!
One of the client requirements is that the server generate files and store them on a special folder. This files created can not be modified by users or deleted.
So the only way I thought is to generate this files with elevated privileges so a normal user can't delete or modify them.
But the question is how can I generate a file with this privileges that normal users can interact with this files... only download from server.
I use this code to generate the file... But I don't know how to configure it for elevated privileges.
This is the button which generate the file and allow to download it:
Protected Sub ibtGenerar_OnClick(ByVal sender As Object, ByVal e As ImageClickEventArgs)
oArchivoTelecredito.NombreArchivo = txtNombreArchivo.Text
oArchivoTelecredito.SesionDetalleArchivosTelecredito = New List(Of DetalleArchivoTelecreditoBE)
Dim oArchivoTelecreditoSL As New ArchivoTelecreditoSL
Response.AddHeader("Content-disposition", "attachment;filename=" & oArchivoTelecredito.NombreArchivo & ".txt")
Response.ContentType = "application/octet-stream"
Response.BinaryWrite(oArchivoTelecreditoSL.GeneraArchivoTelecredito(oArchivoTelecredito, Server.MapPath(oArchivoTelecredito.NombreArchivo)))
Response.End()
End Sub
This is the function which create the file on server:
Public Function GeneraArchivoTelecredito(ByVal telecredito As ArchivoTelecreditoBE, ByVal ruta As String) As Byte()
Dim lineas As Integer = telecredito.SesionDetalleArchivosTelecredito.Count + 1
Dim registro(0 To lineas) As String
registro(0) = Me.ObtenerCabeceraArchivoTelecredito(telecredito)
Dim archivo = ruta & ".txt"
Using escritor As New StreamWriter(archivo)
For index = 0 To lineas
escritor.WriteLine(registro(index))
Next
escritor.Close()
End Using
Dim lector As FileStream
lector = File.Open(archivo, FileMode.Open)
Dim bytes(lector.Length) As Byte
lector.Read(bytes, 0, lector.Length)
lector.Close()
Return bytes
End Function
If you want to set the file to be read-only then you can use
File.SetAttributes("PathToFile", FileAttributes.ReadOnly).
You could also set the permissions on the directory itself instead of the individual files - see this post: https://serverfault.com/questions/3878/is-there-a-way-to-prevent-a-file-from-being-deleted
I am trying to import some data from an excel spreadsheet, using VB.net
my steps are:
first the user uploads the file to the server
then i want to read the file from the server to then populate a gridview
this is what i have:
Protected Sub btnUpload_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnUpload.Click
Dim filepath As String = ""
If FileUpload1.HasFile Then
Try
If (FileUpload1.PostedFile.ContentType = "application/vnd.ms-excel") Then
Dim filename As String = Path.GetFileName(FileUpload1.FileName)
'Session("userid") & "-" & Date.Now()
filepath = "\excel\" & Session("userid") & "_" & Now.Date().ToString("Mdy") & "_" & filename
FileUpload1.SaveAs(Server.MapPath("~/") & filepath)
ReadExcel(filepath)
Else
StatusLabel.Text = "Only Excel file types are accepted"
End If
Catch ex As Exception
StatusLabel.Text = "Upload status: The file could not be uploaded. The following error occured: " + ex.Message
End Try
End If
End Sub
Sub ReadExcel(ByVal filepath As String)
Dim MyConnection As System.Data.OleDb.OleDbConnection
Dim DtSet As System.Data.DataSet
Dim MyCommand As System.Data.OleDb.OleDbDataAdapter
MyConnection = New System.Data.OleDb.OleDbConnection("provider=Microsoft.Jet.OLEDB.4.0;Data Source='" & filepath & "';Extended Properties=Excel 8.0;")
MyCommand = New System.Data.OleDb.OleDbDataAdapter("select * from [NSTS]", MyConnection)
MyCommand.TableMappings.Add("Table", "Net-informations.com")
DtSet = New System.Data.DataSet
MyCommand.Fill(DtSet)
gwResults.DataSource = DtSet.Tables(0)
MyConnection.Close()
End Sub
the error happens with "MyConnection", it tried to look on the "C:/" instead of on the server:
'c:\excel\3_41911_Sample.xls' is not a valid path. Make sure that the path name is spelled correctly and that you are connected to the server on which the file resides.
how can i set the OleDb connection to get the source file from the server instead?
thank you!
nevermind, i got it
i added: Server.MapPath("~/") & filepath and now it works. however, now i'm getting the error:
The Microsoft Jet database engine could not find the object 'NSTS'. Make sure the object exists and that you spell its name and the path name correctly.
NSTS is the name of my first spreadsheet. what am i doing wrong? :(
i was missing a studip dollar sign :) ahh, it all works now!
"select * from [NSTS$]"
thanks!
Use a $ in your sheet's name in the query:
"select * from [NSTS$]"
Your c:\excel\ path is not local path but it is path local to where you are running your application.
If you are running this application from local machine, In order to map c:\excel\ path, you should either map server drive to your windows and use that drive name OR use \\excel as path value.
First - do you know exactly where on the server path the file is being saved to? I'd begin by hardcoding the path to make sure that there isn't anything else squirrely going on.
Looking at your code you're saving the file here...
FileUpload1.SaveAs(Server.MapPath("~/") & filepath)
So... first, are you sure it's saving there? If so then look as where you're reading the file with this call...
ReadExcel(filepath)
Have you tried -
ReadExcel(Server.MapPath("~/") & filepath)?
I have the following data that basically I only need a few bits of information from:
Resource:X - Y;Z - Å;Type:(all) From Date:
07/12/2010 - To Date 07/12/2010 Sort
by:Time Include Referring
source/physician:No Footer:Default
Criteria:None
","Appointments","X,
Y","ZAssociates","Monday, July 12,
2010","Time","Patient Name","Patient
ID","Appt. Type","Ref. Source/
Physician","Phone","Type","DOB
","Z, X","Y","7/12/2010
12:00:00AM","Time","Patient
Name","Patient ID","Appt.
Type","Phone","Type","DOB "," 7:30
[snip]
The only things I need from this are:
Patients Name
Drs Name
Patients Phone Number
Appt Time
Appt Date
and the rest of the information I can discard. A customer uploads this as a .csv file (even though it really isn't as you can see) and I'd like to parse the needed information and post that to my SQL database and discard the rest. I think I can do this with a dataset but I've never built that before. The fields from the customer will always be the same and the fields I will need will always be the same.
Also, the date time has to be in the format of yyyy/mm/dd:hhmm and the phone number always has to have 512 as a prefix. Here is the code I currently have for my site:
Imports System.IO
Imports System.Data
Imports System.Data.SqlClient
Partial Class _Default
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
End Sub
Protected Sub Submit1_Click(ByVal sender As Object, ByVal e As System.EventArgs)
Dim SaveLocation = "\\xxxWEB3\wwwroot\Webfile1\Reminders\Doug_Ancil\doug.csv"
If UploadFile(SaveLocation) Then
'the file was uploaded: now try saving it to the database
SaveToDatabase(SaveLocation)
End If
End Sub
Private Function UploadFile(ByVal SavePath As String) As Boolean
Dim fileWasUploaded As Boolean = False 'indicates whether or not the file was uploaded
'Checking if the file upload control contains a file
If Not File1.PostedFile Is Nothing And File1.PostedFile.ContentLength > 0 Then
Try
'checking if it was .txt file BEFORE UPLOADING IT!
'You used to upload it first...but the file could be a virus
If File1.FileName = ("doug.csv") = False Then
'The file is not the expected type...do not upload it
'just post the validation message
message.Text = "Sorry, thats not the correct file."
message2.Text = "Please locate and upload 'doug.csv'"
Else
'The file is a .txt file
'checking to see if the file exists already
'If it does exist Deleting the existing one so that the new one can be created
If IO.File.Exists(SavePath) Then
IO.File.Delete(SavePath)
End If
'Now upload the file (save it to your server)
File1.PostedFile.SaveAs(SavePath)
'After saving it check to see if it exists
If File.Exists(SavePath) Then
'Upload was sucessful
message.Text = "Thank you for your submission."
fileWasUploaded = True
Else
'the file was not saved
message.Text = "Unable to save the file."
End If
End If
Catch Exc As Exception
'We encountered a problem
message.Text = "Your file was not in the correct format. Please contact Customer Service at xxxx-xxxx-xxxx."
End Try
Else
'No file was selected for uploading
message.Text = "Please select a file to upload."
End If
Return fileWasUploaded
End Function
Private Sub SaveToDatabase(ByVal SavePath As String)
Try
Dim sqlQueryText As String = _
"BULK INSERT dialerresults " + _
"FROM '" & SavePath & "' " + _
"WITH ( FIELDTERMINATOR = ',' , ROWTERMINATOR = '\n' )"
' and bulk import the data:
'If ConfigurationManager.ConnectionStrings("Dialerresults") IsNot Nothing Then
'Dim connection As String = ConfigurationManager.ConnectionStrings("Dialerresults").ConnectionString
Dim connection As String = "data source=10.2.1.40;initial catalog=IVRDialer;uid=xxxx;password=xxxxx;"
Using con As New SqlConnection(connection)
con.Open()
' execute the bulk import
Using cmd As New SqlCommand(sqlQueryText, con)
cmd.ExecuteNonQuery()
End Using
End Using
'Else
'message.Text="ConfigurationManager.ConnectionStrings('Dialerresults') is Nothing!"
'End If
Catch ex As Exception
message.Text = "Your file was not in the correct format. Please contact Customer Service at xxxxxxx."
End Try
End Sub
End Class
Thank you,
Doug
Personally, I'd use a library like FileHelpers to parse/load the data then whatever my typical means of data access for this app is to update it.