I want to create thread for reading data from Excel. I found this link.url...I download the sample project and tried to run the project.First I build the project using visual studio 2005 and add reference the NetFX20Wrapper.dll..When I run the project, I got error "ActiveX Component cannot create obect" in the Line "Set background = New NetFX20Wrapper.BackgroundWorkerWrapper"
View 2 RepliesI'm developing application in VB.NET 2008.I'm reading data from Excel through OledbConnection. Here data are reading sometimes perfectly but sometimes it is missing to read some data.
Example :In Excel ,I have 79 columns in excel and 4 rows , first 3 rows are headers so after import i'll delete that rows and actual data starts from 4, so here i have only one row.After Reading through oledb, that dataset's datatable has only first 3 rows( first row became header and 2 & 3 row only in datatable, its ignoring 4th row)
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I'm a new VB programmer, although I have a decent background in java.Anyways, I'm learning VB and I'm trying to read data from an Excel file using VB 2008 and can't figure out how to accomplish this. I can't seem to get any data from the Excel spreadsheet to display in a simple Windows form. Also, there's a decent amount of data in the spreadsheet so I was wondering if it makes sense to just read data as needed from the excel spreadsheet or if there was some type of data structure that I could import the entire Excel spreadsheet into and do my analysis from there.
View 1 RepliesI have a question about reading data from txt file and importing(transfer) to the existing excel file.for example I have "test.text" which includes some numbers listed below.[code]I want to put each number to separate excel cells by using Vb.net.
View 1 RepliesI have never read from an excel file in VB.NET before so sorry if anything is off.I am downloading an .csv file from a vendors ftp service that has 8 columns ( style # - mfr.item # - description - metal type - availability - center weight - total weight - retail value )I am trying to retrieve all data in the rows bellow style # and retail valuethere are roughly 4,649 rowsI am not sure how to do this.
I load the excel file using the microsoft.office.interop.excel:
Dim eApp As excel.Application
Dim eBook As excel.Workbook
[code]....
I just tried to read data from an excel sheet. I just found some code on net. But it is not working for me. I'm unable to debug, since i don't know how to make use of the ADO.Net [Code]
View 3 RepliesI have a dictionary object (let's call it _do) I am using to cache some values for use in a multi-threaded program. I have a single controlling parent thread, with a timer function _doTimer() which can kick off child threads with a new instance of class MyThreadObject in each. My parent thread has _do as a property and with each time _doTimer() gets called, it may or may not repopulate _do depending on cacheflag settings. I pass a reference to _do to each instance of MyThreadObject and those threads at some point read the values of _do but DO NOT write to it.
What I want is to ensure that the child threads do not try and read _do whilst the parent thread is writing to it. Same thing but very slightly different -> I also don't want the parent thread to write to _do whilst the child threads are reading from it. However there is no problem with 1 child thread reading the values of _do at the same time as another child thread is reading the values - so ideally I do not want each child thread to completely lock out read access, only locking out Write access.. The code is roughly like this:
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G'day all, I've been on google for far too long trying to figure this out, so hopefully somebody can point me in the right direction. I'm trying to write a program that will open an Excel spreadsheet and read data from specific cells while preserving datatypes, so that I can write the data to an XML file. The basic functions I need to perform reduce to:
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I am trying to build an app that can search column A in an excel document (with textbox control). In column B, I have info about the column A items. When a column A item is searched, I would like a textbox (or similar) to display info about it from column B.
View 6 RepliesI am reading in data from an excel file that is only viewed inside the program. This excel file is being populated by data from multiple PLCs (7) through DDE links via RS Linx Gateway. I would like this data to be written to two different excel files and specific sheets within those so that it can be viewed later on.
My program has a form that will allow the user to view the data live, meaning they look at the first excel file from the program so that they are not able to edit the DDE links or change the file in any way. The other excel files (there will be two, one for good parts, one for bad parts) have specific sheets for each part and each tester station. For example, if the part is a ABC part, and it is a good part, and it was tester on tester station 1 then it needs to be saved to the good parts excel file, in the ABC sheet and in the good tester station 1 sheet.
If part XYZ comes along and is a bad part (fails testing) then it needs to be saved to the bad parts file, the XYZ sheet and the bad tester station 1 sheet.I might have added more detail than is needed to solve the problem but I thought I would add it anyways to help you all understand my problem a little better.
I have some trouble with opening a excel sheet and getting some data out of it.
I want my program to have a button, when pressed, gives a "select excel file" popup and then load the data from some cells into my sql database.
So, when opening a excel file the program should get the data from cell D3 to D8 and put that into the sql database.
I now have the following, but that will only open the excel file.
Public Class Form1
Dim oConn As ADODB.Connection
Private Sub ConnectDB()
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I want to import data from excel and move that to Datatable in VB.NET 2008. I wrote and working but its taking too long time.. for 1500 records its taking 4.40 min.
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In my application I read data (using data binding) from an Excel spreadsheet into a DataGridView. This works, but the data columns contain text fields (strings). I would like to set the data type for some columns to "Date" and Decimal. I cant do this on the DataGridView (error: cant change properties for data-bound stuff) and I cant figure out how to do it on the dataset or data-table that I bind to the DataGridView.The following is the code I use to read and bind the data:
Using con As OleDbConnection = New OleDbConnection(cs)
'
'open the OleDbConnection
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The commented out code (below the 'Todo: comment) causes a additional table, but I want to change the table with the data.
I use an OLEDB connection to read from an excel database, and this loop to read in all of the data from each of the columns
While reader.Read()
For i As Integer = 0 To reader.FieldCount - 1
temp = reader(i).ToString + ControlChars.Tab
output_file.Write(temp)
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Some of the columns contain date information, which are read in fine (usually as a string "2/20/2011" or so), but the headers of those columns are read in as a blank "". The headers for all the other columns read in fine, but not for the date containing columns.
I am trying to read some data from an Excel 8.0 worksheet using OLEDB thusly:(Warning - contains curly braces)
Code:
DbProviderFactory factory = DbProviderFactories.GetFactory("System.Data.OleDb");
using (DbConnection connection = factory.CreateConnection())
{
[code]....
The problem is that for some columns it sets the data type to be Double even though the spreadsheet column format is "Text" and teh column contains non-numeric data. Then when it gets to that cell it returns DBNull instead of the text value.
i just got 1 question how do u create a (in excel ) variable table (database) inside a function which could be called for filling and reading through "for to next" loop module
View 2 RepliesI'm creating a Client Server application which involves theServer running some scripts in clients and getting back results in an automated way. In Server, other than Main thread, i have 2 worker threads, a) one monitoring response from clients and b) the other scheduling next available job to respective client which executes that job. The issue here is ,I want these worker threads to write the status of their work in the UI(which comes under Main Thread). Also i need to write things in worker thread in a Data table and Rich Text Box in Main thread. But, I can't do so, since it has been blocked to access one thread's function or property directly from others. Is there any work around to do this?
View 8 RepliesI want to reading in a excel file and extract the sCodenumber sDescription ans the sStatus and store them in a array : StatusComposeArray(5200) As MyCompose. After this I need this array for comparing outside this class. But as can you see the array is defined inside the sub: ReadingIn_ExcelFilesCompose [Code]
View 2 RepliesThe following code works fine but seems to leave instances of excel.exe running in the background. How do I go about closing out this sub properly?
Private Sub ReadExcel(ByVal childform As Fone_Builder_Delux.frmData, ByVal FileName As String)
' In progress
childform.sampleloaded = False
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I have a program that tracks packages. Shipment and package entities are persisted in SQL database, and are displayed in a WPF view. Upon initial retrieval of the records, there is a noticeable pause before displaying the new shipments view, and I have not even implemented the code that counts shipments that are overdue/active yet (which will necessitate a tracking check via web service, and a lot of time).I have built this with the Ocean framework, and all appears to be doing well, except when I first started my foray into multi-threading. It broke, and it appeared to break something in Ocean... Here is what I did:
Private QueryThread As New System.Threading.Thread(AddressOf GetShipments)
Public Sub New()
' Insert code required on object creation below this point.
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I'm creating a reporting web page as part of a standard VB.NET web application. The page is data driven, with jquery making calls to a web service local to the application to get values of elements that are dynamically created in the DOM. Ultimately these dynamic elements and their values are all wrapped up in a JSON object, so that part of the client side is fine.
Right now, I can pass that JSON object to a method in the web service which creates an SQL Data adapter from the values and queries a database. My ultimate goal is to have this client JSON data be used to query the database and construct an excel file to send back to the user, or failing that a CSV file.
It's my understanding (from working with PDF file generation) that this type of function can only be done on the server side of the web application, not even from the web service (i.e. I can't have the web service return an array of bytes and have JavaScript/jQuery present that as a file).
So, how do I go about this? Now I have my JSON object on the client side, where should I be sending it, how, and how do I go about returning my file?
I've read about either storing the JSON in a hidden field and having the server take the elements value and go from there, or using AJAX to send the JSON to the server just before a postback is made to fire off the server-side function to run the query and return the data.
I just need a little guidance, and a little help understanding where to use the hidden field, or what I am actually doing with the pre-postback AJAX call.
I have a simple WPF windows application trying to read a serial port with the System.IO.Ports.SerialPort. When I try to read the incoming data in the DataReceived event, I get an exception saying that I don't have access to the thread. How do I solve it?
I have this in the WPF window class:
Public WithEvents mSerialPort As New SerialPort()
Private Sub btnConnect_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles btnConnect.Click
With mSerialPort
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I'm having trouble getting a progress bar to update. I'd be okay just with a moving marquee bar. Basically, I'm reading a database routine in a SqliteReader.vb class. I need to use the worker_DoWork routine, but I'm not sure how to expose my variables coming from Form1: graphData, graphComputations, m_debug to the worker_DoWork sub. How is this usually done? [Code]
View 3 RepliesOk, what I would like to be able to do seems simple enough. I would like to be able to create an Excel document with a series of columns that contain data to import into Visual Basic 2008
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I'm learning VB.NET coming from a VB6 and Java background.In my app, I've got a function that validates the fields on a form. All it is doing is reading them, not updating. I've searched and see info about the backgroundWorker class, but all the examples are about updating the fields.I understand the idea of threading and how it works, but have never written code that spawned threads myself. I've always let the language handle it. It seems like a lot of work that I would have to write a sub using the backgroundWorker for every time I wanted to read or update each field. The couple of books I've got that introduce you to the language show you reading or updating the field directly.How do I know what threads are running other than writing the code like I'm used to then running through debugger to figure out what variables are on which thread?
View 2 RepliesI get this error when i request the 'SelectedItem' property of a standard .NET ComboBox control from a BackgroundWorker control.
I know why this exception is raised, however, i thought that read-only operations to controls from different threads were safe?
I know i can turn this off using Form.CheckForIllegalCrossThreadCalls - but i want to make sure that readonly calls from non-ui threads are actually safe or not?
I'm trying to follow the technique discribed by jmcilhinney in this HTML [URL]..I have all the drawing code in the .Paint event. Reading the above mentioned thread I would need .Invalidate(all or parts of the picturebox) AND .Update() in order to repaint (all or parts of) my PictureBox, however in my case it works without .Update. Am I doing something wrong?
View 5 RepliesAll the code i found for multi-threading is complex and not clear.What i want to do is creating a thread for reading and analyzing a big text file on Form_Load event, so that the form UI building continue without waiting for reading and analyzing the file finish.
View 2 RepliesIn one application, I need use 4 simultaneous threads.When the threads finished, I need to update the text of a TextBox.So, I create 4 Textbox, and I wanna the threads change the text to FINISHED.Each thread change one distinct TB.I use this "example"
Dim Terminados As Integer = 0
Private Sub frmEnviarMensagem_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Timer1.Enabled = True
Timer1.Start()
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The problem is, I have an error in the red lines.The error is: INVALIDOPERATIONEXCEPTION "Cross-Thread operation not valid: Control tbPlaca1 Accessed from a thread other than the thread it was created on."I don't use cross threading. Each TB only was accessed for the correspondent thread, and for the "main program".
This is the error message I am getting:
"Cross-thread operation not valid: Control 'Panel1' accessed from a thread other than the thread it was created on." The reason I am getting this error is because I am opening up a new form and then calling these three things:
Panel1.Show()
Label1.Show()
Label2.Show()
why I get this error message because it doesn't occur normally if I open Form2 after closing Form1, it only occurs when I open Form2 after closing Form4.