Does anyone know if it is possible for data which a user has typed into a text box can remain when the application has been completely close and reopened again, and if all of the new windows can also reopen with the user inputted text.
I have been spending hours trying to work out how to do it but can't find a way!
I'm following a tutorial using serialization/saving records.I can make records, display them ok in a datgridview and then save them ok using serialization. Then I can reopen the programme and reload the dataset from the deserialised file, and show the records ok [code]....
View 1 RepliesI'm following a tutorial using serialization/saving records. I can make records, display them ok in a datgridview and then save them ok using serialization. Then I can reopen the programme and reload the dataset from the deserialised file, and show the records ok - but I cannot add any more records to the datagridview.
Here is my code:
Imports System.IO
Imports System.Runtime.Serialization
Imports System.Runtime.Serialization.Formatters.Binary
[Code].....
how do you save the value of a variable for later if the application is closed and reopened in winforms, vb.net?
View 2 RepliesHi,
I have a program that has over 100 labels and over 40 textboxes. I was using the code below to save the text. However, when I open it, some of the text is in the wrong spot (for a label or textbox) and some of the text that shouldn't have been saved is. Is there a way that I can get all these labels' and textboxes' data saved? I would like to stick to the code somewhat if thats possible. I may be looking in the wrong direction too as I am very new. Thank you.
Private Sub SaveAsToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SaveAsToolStripMenuItem.Click
Dim myStream As Stream
Dim saveFileDialog1 As New SaveFileDialog()
saveFileDialog1.Filter =
"txt files (*.txt)|*.txt|All files (*.*)|*.*"
saveFileDialog1.FilterIndex = 2
saveFileDialog1.RestoreDirectory =
True
If saveFileDialog1.ShowDialog() = DialogResult.OK Then
myStream = saveFileDialog1.OpenFile()
If (myStream IsNot Nothing) Then
Dim myStreamWriter As StreamWriter = New StreamWriter(myStream)
myStreamWriter.WriteLine(txtName1.Text.ToString)
myStreamWriter.WriteLine(txtName2.Text.ToString)
myStreamWriter.Flush()
myStream.Close()
End If
End If
Private
Sub OpenProjectToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OpenProjectToolStripMenuItem.Click
Dim myStream As Stream = Nothing
Dim openFileDialog1 As New OpenFileDialog()
openFileDialog1.Filter =
"txt files (*.txt)|*.txt|All files (*.*)|*.*"
openFileDialog1.FilterIndex = 2
openFileDialog1.RestoreDirectory =
True
If openFileDialog1.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
Try
myStream = openFileDialog1.OpenFile()
If (myStream IsNot Nothing) Then
Dim myStreamReader As StreamReader = New StreamReader(myStream)
txtName1.Text = myStreamReader.ReadLine()
txtName2.Text = myStreamReader.ReadLine
myStream.Close()
End If
Catch Ex As Exception
MessageBox.Show(
"Cannot read file from disk. Original error: " & Ex.Message)
Finally
If (myStream IsNot Nothing) Then
myStream.Close()
End If
End Try
End If
I have a program that has over 100 labels and over 40 textboxes. I was using the code below to save the text. However, when I open it, some of the text is in the wrong spot (for a label or textbox) and some of the text that shouldn't have been saved is. Is there a way that I can get all these labels' and textboxes' data saved? I would like to stick to the code somewhat if thats possible.
View 25 RepliesUsing VB.Net, how can I save values from a textbox and checkbox when the application is closed? When the user opens the application again, the textbox and checkbox should be filled in with the same values as before.Do I have to save these values in a database, or what other options are there?
View 3 RepliesI have a problem reading data from an RFID-reader. I connect to the reader by tcp and wait for DataAvailable to be true, then reading the data until I got a end of data character. Then I just go back and waiting for a new DataAvailable. This is done in a own thread for the function.
There seems to be some kind of timeout, If I don't got any data in a couple of minutes, then it just sits there in the do/loop waiting for DataAvailable. I hold the card to the RFID reader, it beeps, but there is no data available. I don't get any exeptions, and the information says that the clientsocket is still connected. Are there anything more I can check?
If I put the card to the reader in a minute-interval it seems as this will never occur. So 2-3 minutes idle:ing seems to do this.
Here are my code to read data from the socket, I have taken away some irrelevant code:
Sub test(ByVal ip As String, ByVal port As Integer)
' this sub is meant to run forever
[CODE]......................
Im working on a HSD 32 bit data bus to serial converter via a microcontroller. Now first I want to make a sort of data sniffer to read the data bus (32Bit) .All on the controller side is working and the stream of bytes are coming in via RS232 as 4 bytes in HEX like FD,A5,45,8B . I already converted the bytes in Dec and ASCII to determine what is passed true the bus and how fast and stuff.. Now that is all correct and working very well if the LSB (least significant bit) of the 32 data bus is Data line 0 and the MSB (most significant bit) is Data line 31 but if that is not the case I need to invert the 32Bits (like as I would invert the connector on the bus) . How do I best do this using the 4 bytes I send from the micro controller.
Example:
(MSB) 01001000 01100101 01101100 01110000 (LSB)
HEX= 48 65 6C 70
DEC= 72,101,108,112
ASCII= H E L P
I need to invert it with a button to:
(MSB) 00001110 00110110 10100110 00010010 (LSB)
HEX= 0E 36 A6 12
DEC= 14,54,166,18
ASCII= (SO) 6 : (DC2)
I need to control a device with a GPIB port. I have the commands that I need to use to do this; but I don't know which is the sintaxis in Visual Basic.
For example if I need to send a instruction like "START:0.01" to the external device which are the libraries that I have to include?, how should I write the programming line to do this?
The main tasks that I need to program are sending data, receiving data, and saving data
I have a basic application that allows pre-defined users to use the application.The Username & passwords along with some other basic user info is stored in a simple access dbIn my application I want a user to login, Username & PasswordI create a connection string, a data adapter and a dataset, I then need to validate the password the user has entered.Would it be best to query the access db directly, or the dataset?
View 5 RepliesI am having an issue on the listbox when the new data value equal to previous data then = to "0". However, I want if the new data value( A ) is equal to the previous data( B ) then ( A ) equal to ( B ).
Delegate Sub ListBoxUpdater(ByRef listbox As ListBox, ByRef str As Object)
Private Sub OnQuoteUpdate(ByRef QuoteUpdate As LingLib.structQuoteUpdate)
UpdateListBox(lbBox, QuoteUpdate.tQuote)
End Sub
[code]....
My problem is when the new data comes out from the API, if it is equal to the previous data and it will appear 0. But what i want is the new data comes out is 0 and it will equal to previous data. e.g: first data comes out is 12.00, in above case, if the second data comes out is 12.00 but it will shows 0 which means unchanged. But in my case now, i want if the first data come out is 12.00, then if the next data is unchanged (0) and it will appear 12.00 and so on.
I am currently working on a API. I am having an issue on the listbox when the new data value equal to previous data then = to "0". However, I want if the new data value( A ) is equal to the previous data( B ) then ( A ) equal to ( B ).
Private Sub UpdateListBox(ByRef listbox As ListBox, ByRef str As Object)
If (listbox.InvokeRequired) Then
Me.BeginInvoke(New ListBoxUpdater(AddressOf UpdateListBox), listbox, str)
[code]....
how to connect to a database and retrive data in a table using oledb data provider in Microsoft access?
View 2 Repliesi want to create a table that include a current year data and as well as previous data to be compare. here is the example of the table that i want to create: but i want to compare one of the annual data with the previous year. as example i want to compare between the data of current AR of 2007 with the current AR for 2006, Current AR of 2006 with current AR for 2005 and go on~, but i have no idea how to do it.
View 1 RepliesI have two data tables. the second related to the first. Using a datagridview for the first table I am able to enter and save data ok. if I run the code twice in a row the data is still there. When I edit the data in the related table in it's own datagirdview the data is there and displays correctly, but on running the code a second time the related data is lost. In both cellendedit events I am using
Me.table.Update(Me.FigsDataSet.table)
Me.Validate()
I have just started with vb and would like to know if there is a way to input several boxes of data on one form and display individual pieces of that data on several other forms at timed events in the future?
View 1 RepliesWhat I am trying tot achieve is the following:User inputs data in one form that saves to the dataset table no problems. On an edit screen I want the current data saved to appear in this page within all the relevant fields but when saving I want this data to add to the dataset table as an additional line of data so the transaction records are kept.I want to add a new datarow regardless of it saving one change or all 7 changes that are possble.
e.g. Line 1 - user inputs 7 cells of data Line 2 - user amends 2 cells of data Line 3 - user amends 1 cell of data an so on. Unfortunately the terminology for certain items above may not be correct as I am still new to this programming and still on a massive learning curve.At the moment I do not have the code for what I am trying to achieve as I really dont know where to start with it.I am currently able to save the data and have it appear in the "edit" panel however only the cells changed are saved an it overwirtes the initial input.
[code]...
In VB.NET I would like to create a complicated data structure with multiple types of data stored in an array like format (see below). I am trying to create a data structure that would look something like this: [Name; xLoc; yLoc; zLoc; [Jagged Array]] Note: Name needs to be dimensioned as a string, xLoc and so forth as integers. The Jagged Array would look like this:
[Code]...
I just want to display data in a DataGridView (from SQL - already made the connection) based on what is selected in a ComboBox (data that is also coming from SQL). The 2 are separete on the form. I am using VB 2010.
This doesn't work for me:
objCommand2.CommandText = "SELECT ProductID, Name, Color, Size, ListPrice FROM SalesLT.Product WHERE ProductCategoryID = " & cbCategory.SelectedValue
[code].....
I'm currently working on a project where I am transmitting data from a comm device via the serial port and resorting the raw data (in binary) to its respective ascii values. The problem I'm facing is determining the most efficient method to accomplish my goal. Essentially, I have 68 bytes coming in, the first and second bytes represent the page and packet number and the data itself ranges from 3 to 64, the remaining for my checksum.
What I am needing to do is, grab 50 consecutive bytes per variable in my array, and that is where I'm confused. I have easily pulled my 3-64 bytes and stored that data to a string. I just don't know the most efficient method to accomplish my goal. Should I write directly to file all my data, as there are like 8 pages, of 128 packet data. [Code] I can capture the the first 50 by using a for-loop easily, but what would be the preferred method to track what data chunk I've taken? The more I think about it, I think I may just want to write to file, all my data, and then just take them back to back in 50 byte chunks. Is that the most efficient method?
Im getting that error in the da.Fill(ds)
Imports System.IO Imports System.Data.SqlClient
[Code]...
i just write code for application, in which data is get by user and entered data is to print in a particular format?give me a code for vb.net button by which after click on it will print entered data?
View 1 RepliesModifying data with the ListView's EditItemTemplate by programmatically settings its DataSource property and calling its DataBind method. I don't have option to use data source control for ListView. All ListViews are bound with data from code-behind. So, I have to handle the Edit/Update mode of ListView manually. [Code]
View 2 RepliesI am new to VB.net. I want to read and input file and store that data to an SQL Server database. Do you have an sample code that do such?
View 1 RepliesI got the System.Data.DataRowView when I tried to select the data from sql database. These are my code:
......
myCommand = New SqlCommand("SELECT FirstName +' '+ LastName FROM tblVisitor", myConnection)
myAdapter = New SqlDataAdapter(myCommand)
[Code].....
I'm trying to connect a VB application (2010) to an MS Access DB by adding a data source from the data menu but I receive this error message "The connection you selected uses a local data file that is not in the current project.Would you like to copy the file to your project and modify the connection ?
If you copy the data file to your project, it will be copied to the project's output directory each time you run the application" and the options are (yes , No , Help)
If I choose Yes I will not be able to make the application 'device independent ' since it will not be copied under the bin , and if I choose No , changes won't be applied to the DB
I have a modbus TCP device that I have managed to connected to through my VB source code.
I want to poll (continueously read) data from certain registers of the device, and store the polled data in a file (text,csv, excel).
I'm just trying to create a graph where the user can input data into textboxes and then plot the data. I am attempting to use Zedgraph, but open to other suggestions. The program below creates a plot, but it won't update when the textboxes are updated.
Imports ZedGraph
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[code]....
I have an Address Book project with a listbox. The listbox is bound to the database via the little arrow pop-up box in the corner of the listbox. I have the DisplayMember set to FirstName, and obviously only display the First Name of the contact in the ListBox. Is there an easy way to change it so that it displays the First and Last names? I can't change the binding because I need it to get the ID of the record selected.Here's the basis of my code...
Private Sub MainForm_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
'TODO: This line of code loads data into the 'CompanyDataSet.Contacts' table. You can move,
[code].....