I'm using ADO.Net to work with an Excel Document. Essentially, I'm looking up values in a table called "source" and creating a new table called "result" which will be populated with the results of my query.
I have a couple of questions.A) How can I check if a table exists and create a new one if it doesn't? B) Is a table the same as a sheet in Excel?[URL]...
I am trying to write(what I thought would be a simple piece of code. I was wrong.
What I am trying to do is to get an application to check if a file exists, However, I have it wrong as the file obviously does exists, but when I run the application it tells me it does not.
Imports System.IO
Public Class check
Dim checkfile As New FileInfo("C:\HelloWorld")
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I'm using then next method to check if a directory exists but it seems it doesn't work.
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im trying to make code to check if a file with the same name exists twice in the same dir one with .dds and one with .veh file extentions and if they do put in a listbox but if only one exists then it puts it in another listbox i have made code to filter .dds in to one listbox and .veh in another but i dont know how to make the "check" if they are both there
this is the code i have to split them at the mo
For Each files In dir
Dim path() As String = files.Split("\")
Dim chunk As Integer = path.Length
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but i wanted the Else for the .dds files that dont have the matching .veh file
I am trying to check whether username entered by user is already exist or not in database. But, I dont know how. The codes are below.
If TextBox3.Text = TextBox4.Text Then
Dim conn As New SqlConnection()
Dim cmd As New SqlCommand()
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I think this is a really simple question to answer but I can't find a better solution. Basically I am importing data from an external source and as I go through importing each for I am doing a for loop to see if the row already exists; this is taking a life time and I feel it is a very simple way of doing it. Is there a better way to see if a row already exists using specific columns and key indexes?
View 5 RepliesI haven't used System.IO before, and I'm a little stuck.I need to check if a file exists, for example C:Documents and SettingsverraineDesktopSURNAME Firstname v1.docx, if this file exists the filename has to become v2, and so on. Usually there will only be a v1, but in the case that a clients position changes we have to be able to save the new version without overwriting the old one.
How would I be able to do this efficiently? I'm uncertain to say the least. Because, if I manage to find out how to save the file as a different number, that's alright, but if that next number exists as well? I can only think of ways to do this that require a lot of code.
i have a checkbox on a form, which is of type boolean in the database .when the user check the checkbox, before the data enters the database, the program should check if there exists already a "1" on the database for this field.If so the user is not allowed to check the depot.
View 5 RepliesCompletely new to ASP.net
Page Language="vb"
Microsoft .NET Framework Version:2.0.50727.3603; ASP.NET Version:2.0.50727.3082
I want to check on the server for the existence of an image, then if it does exist, display the image wrapped in other code. E.g.
if "/images/name.jpg" exists then
<div><img src="/images/name.jpg"></div>
else
Do nothing.
Seems really simple to me but NOTHING I have tried has worked (compilation errors). I've tried examples using system.io, DIM stuff with 'FileInfo', Set fs. FileInfo examples produce 'not defined' errors, 'Set' says it's outdated and not used anymore and so on.
I want to check if an Outlook folder exists, if it doesn't then create it & if it does then carry on with other code. I can create the folder as a sub folder of the Inbox but once it is created I get an error because it is still looking to create when it's already created. I have tried to capture the error but still no joy.
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I am having a ton of trouble trying to check if a record exists. I continue to get a data mismatch on my command.ExecuteScalar().
Code:
Protected Sub btnRegister_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnRegister.Click
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I've created the following function and thrown it inside of a timer:
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It works, but it keeps trying to open media player for each process it looks like. I need to continuously run the function so that Media Player opens when it's closed.how to make sure it opens only once when the process doesn't exist?
I'm checking is a file exists as follows.
If txtGradeObs.Text = "" Or Dir(txtGradeObs.Text) = "" Then
MsgBox("Specify the Grade job of Obstructions", vbExclamation, MsgBoxTitle)
Exit Sub
End If
I get an error if the drive does not exist - i.e. G: rather than C:. It used to work in VB6. How can I get it to work.
I'm trying to download files using the Net.WebClient call to DownloadFile
Using client As New Net.WebClient()
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Is there a polite way I can ask for the file instead of calling DownloadFile, and handling the exception ?
I am adding the text of a label into a datagridview. But before i do the insert, i want to check if the text does not already exist in the datagridview.
View 1 RepliesI have been on MSDN about this and searched but it's not quite telling me what I'm after. I've extracted a list of file names from an Excel spreadsheet and want to check whether they all exist in a directory which a user can select in a text box. It feels like I'm nearly there with it but currently my listbox is displaying everything, I want it to just show the files that are missing. I'm a beginner so I'm not exactly sure if I'm even telling it to compare the two things properly, I've tried a couple of ways of checking if a file exists but neither seem to work.[code]
View 1 RepliesI'm using the following code (System.Data.SQLite within VB.net)[code]...
I know the table exists because I can write to it via the command line through sqlite and through Autoit and can see it and edit it in the SQLite browser when I open the database. I don't understand why VB can't see it (I know it sees and opens the database file just fine).
I developed a package in vb6.0 backend as oracle 8.1.7, i instaled my package on nearly 50 client systems, every thing is fine except ,in some screens when iam saving the record it displays the message "Table or view does not exists", but this error is occuring only on thoes systems using other than Windows 2000 OS . What might be the problem
View 5 RepliesI have a tenant details form that has a field called TenantID, I also have a Lease table that also has a TenantID field, what I want to do is click the lease button, check to see if the lease already exists, if it does open the lease form to that record. If not then open the lease form to a New record so the user can enter all the information for that lease.
I am trying to use the below code but am having a little trouble understanding how it all works. What needs to be declared, what doesnt
HTML
Private Sub btnLease_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLease.Click
Dim fm2 As New LeaseDetails
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I'm trying to do an if statement to determine whether a value entered in a text box exists within a column..
View 6 RepliesI was wondering if there is a way to programatically check and see if a sheet exsists in an excel workbook?
Basically what I am doing is checking if an excel document exists, opening it up and checking if the specified sheet exists. I am currently unaware as to how to check and see if the sheet exists.
UPDATE
I have been given some good code to make this work. All i am missing now is the correct imports.
I have searched and found this import :
Imports Tools = Microsoft.Office.Tools.Excel
But for some reason that is not recognized. Do I have to configure VS somehow to make it work? Or am I just using the wrong import?
I am looking to programme a button to check if an entry from a textbox exists within a table.
This will done via a button.
how I would code the button to make it query the table?
I have an 'invoices' table with a column for the invoice number.
When adding a new invoice, I would like to check if it already exists. If it exists, produce a MessageBox to the user that there's already a record with this number.
I'm using Visual Basic 2010 and SQL Server 2008.
i am trying to search a table in an access database to see if the value of a text box exists in it. I have this so far:
Dim myConnection As New OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; Data Source=" & Application.LocalUserAppDataPath & "\Database" & "\Student Aid Database.mdb")
myConnection.Open()
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I wont to be able to check if a table exist, if not i wont to create it...
This is the code i use for connecting...
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Have a method who gets data from one table, put the data into variables before it it returned into the same table with changed ID etc. My problem is that it adds the first row without any problems, but when it is supposed to add row number 2 the error says tha the row allready exists in the table. and I can not understand why. I have put in a couple of messageboxes to se that the ID is changing and that the ordreID is correct and changing as they should and they do, but stll I get that errormessage.
My code looks like this:
Public Sub Ordreupdate()
Dim dtbl As New DataTable
Dim dt As New DataTable
dtbl = Kalkyle1DataSet.Tables("Ordre")
dt = dtbl.Clone
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Annyone who can see why I get that error?
I'm trying to save an excel file:
vb.net
xlWBook.SaveAs("J:DOWNLOADS.xls")
xlWBook.Close()
xlApp.Quit()
If the file already exists excel will open an message box and ask if you want to overwrite. If I click yes, it works. If I click no or cancel, I get an error:
Exception from HRESULT: 0x800A03EC
How can I tell what button the user clicked?
I'm trying to create an option to select a specific entry in a SQL table if multiples exists. The Sub listed below is for a textbox (MOTxt) and a button (GotMO) for checking an MO# to pull from SQL. Based on the number entered, will populate other text boxes on the page with that row's data. There are exceptions to this, where the MONumber will be entered more than once with different data associated with each entry. So, here's my situation. If we have a duplicate MONumber listed in the table, it will populate the textboxes with the first entry it finds for an update.I would like to create a dynamic dropdownlist (that displays only if multiples are found) displaying the 'Name' field entries for each MONumber found, then once the correct name is selected from that list, to then populate the textboxes with that selected datarow.Here's my code behind:
Protected Sub GotMONum_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles GotMO.Click
Dim da As New SqlDataAdapter
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in my project I insert values into a database, each value needs to be unique, currently I am using the following code to check for the value in the database before inserting, if it exists I loop back and generate another value and check again..
Dim SerialCount As Integer
SerialCount = 0
Dim con As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:UsersMatt-ASUSDocuments im_db.accdb;Persist Security Info=False")
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I'm trying to check username and password by using a For Each Statement. If it validates then messagebox saying welcome appears, if it doesn't a message box saying "incorrect" will keep popping up over and over until it's done looping through the table. How can i correct this and just make it display one time. Also when it does validate a new window will show up with users First and Last name in a textbox, How can I edit users info and then save to db.
Private Sub Button1_Click(sender As System.Object, e As System.Windows.RoutedEventArgs) Handles Button1.Click
Dim data As New datalinq1DataContext
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