Data Is Not Saving In Datasource But Accessible Anyhow
Apr 22, 2011
I took the liberty of creating a small slideshow showing my problem. view it here.
[URL]
As you can see, I start with an empty data table on the data source. I add information to a form and the data appears on other parts of the program through data bound list boxes and such. I can exit debugging mode and re-enter it, and the data is still available.
However, the data is NOT actually added to the data source's table.
If I modify the program at all, the data that is floating around disappears.
I do not understand why this is happening. Apparently I need some kind of code to tell it to write permanently but I have no idea how to go about it. This is something I've been fighting with for over a week. I cannot find any solid information about this online at all.
rewriting a class I use for saving Treeview data to a XML file for use of saving ListView data I can't really figure out the rewrite, I'm stucked, unfortunately Listviews seems to be a big problem for me in general.
Option Strict On
''' <summary> ''' The TreeViewDataAccess class allows the nodes within a TreeView to be ''' persisted to xml for later retrevial. ''' </summary>
I use a gridview to query a DB and pull out results. The View then places the results in the view on the page. I then use a JS function to grab the data. Is there anyway can hide the gridview but still have the data on the page html side?
Currently I am saving data from my applications by saving a text file via a stream reader as a string. I have come to a problem. In my current application, I have an array of the following structure:
I am getting an error message: "Pervasive.data.sqlclient.v is not accessible in this context because it is 'friend.'" This error message appears when I hover the cursor over the "For Each v In qv" line in the following code:
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 sqldatasource with a very simple select statement that should always return one row. I have textboxes on a page that i want to fill with that data from the datasource. how could i do this for textboxes? If there is no data in the database then i want the textboxes to remain empty.[code]....
i am building a database application in vb.net and i started by adding a data source from the DATA in the toolbar. my connection is good and it shows all my tables in the data source panel.
i also see new classes related to my database, like
sakilaDataSet sakilaDataSet.customerDataTable ... and so on.
how do i query and use these ? i googled a lot and i am not able to get this.
Dim cust As sakilaDataSet.customerDataTable = New sakilaDataSet.customerDataTable Dim row() As System.Data.DataRow = cust.Select("customer_id=5") MsgBox(row.Count)
My last try was with the above code, but the row.count always turns out to be zero.
my program has a datalist which list out all the item from datasource and display the detail information on different textbox the problem happened while i click "vitamin a" from datalist, and the "supplier name"will display "daily medicine",then when i click "vitamin b", it will display "sunny medicine",finally when i clicked back "vitamin a", the supplier name still remain "sunny medicine" which mean it does not change from "vitamin b"?
I am using the following code to add a row and data into my datasource.[code]Row # 150 for example, the reason is I want to be able to only add 1 record and if the end user adds another one it overwrites the exisitng one and also be able to retrive that record the next time program is opened.
creating an application using VB 2010 Express. i found data I entered into table were not saved (after I clicked"Save" button)successfully into Microsoft access file which I had added successfully as datasource.These are the codes:
which is supposed to get all the data from my table and set it as the datasource of a DataGridView. You can see where I put in two msgbox's to view how many columns are in the DGV before and after the "update". The first count gives me 22, which is the correct number. After the .DataSource and .DataMember lines are ran, the count jumps to 41 and I have no clue why. All I want to do is clear a dataset, fill it with the new data and set it as the data source of a datagridview. It appears the info is being saved to the table correctly too.
I'm trying to open a crystal report and have the datasource to be a data set but i'm having some problems. here's what I got so far:
My application is using a sqlCe database. On form1, I dragged the dataset, from the datasource tab, onto the form. when the user clicks a button on form1, this is called:
Dim rpt As New WorkLink_Application() 'The report you created. Dim MyCommand As New SqlCeCommand() Dim myDA As New SqlCeDataAdapter()
[Code].....
on the crystal report, i went through the database expert wizard and selected the dataset from Create New Connection-->ADO.Net. I then dragged a field from my table onto the report. When the report is opened, though, the field is not shown.
I am developing a winforms application that will have an offline mode, so that it can access the data if an internet connection (or more accurately, a connection to my WCF service) cannot be established. I have decided to utilize SQL Server Compact edition on the client side of the application & was wondering what the general consensus is on the "best" practice for making the client application (Sql Server Compact) subscribe to the master database (MSSQL 2008).
Management enters information into a web based administration panel that I developed and is stored in a MSSQL 2008 database.After adding / modifying information, they can click a release "datapack" button which will increment a "datapack" version number, which will later be used by the client application to determine if they are in sync or not. When the client application is started, it connects to the internet and determines if the version numbers are in sync. If not, it pulls the information from the server.
That third step is where I'm a bit lost I thought about simply developing a web service that will expose a dataset containing all of the data and just iterating through it doing inserts, but that seems terribly inefficient to me. The full database probably wouldn't amount to much more than 5 MB total, so that led me to think it would be great if when management clicks the release datapack button, it would store the database in a file that could simply be downloaded and would replace the embedded database. Again, I'm a little lost on how that would work. This is my first time working with an embedded database, most of my work has been web/win apps that have real-time access to the data.
I have a question about binding the datasource (MS Access database) to a listbox in a VB form. I have created a listbox and in the datasources explorer I have my datasource say SampleDS. I have several columns inside my datasource, say name, age, address in it. If I select name and drag to the listobx in the form, only the entries in the name column will be displayed in the listbox.
I want to know how to filter the name based on criteria. For example, how do I display names whose age >25?
I have a Query that is in designe mode I have created 4 columns and formatting 4 columns also in datagrid view control now I want to use datasource of dgv control now when i defining datasource property with table then dgv control displaying my predefine columnas and adding 4 more columns in dgv for defining datasource.now presently to avoid autogenerating columns I definie the autogeneration column=false at this situation if i define datasource=table the no data is come up..so my query is it is possible to filled up data in predifned column using datasource property.
I am running VS2008 and am using VB2008. I have created a solution file with a Windows Form Project. It contains one form. I created a class project called DataAccess. I selected that project and created a data source. Now I see the XSD for that data. If display the "Data Sources" window I see the datasource. So far so good. If I select the Windows Form project, and then display the "Data Sources" window I get an empty window with a "Add New Data Source" button/link. How do I make the data sources created in the second project available to the first one?
I have been watching the videos for creating n-tier apps that suggest adding a third project to the solution called DataEntities. I did that. I then click on the XSD in my DataAccess project. Then in the properties of the XSD I change the "DataSet Project" property to point to my new DataEntities project. When I save the DataAccess project the DataEntities project gets a file added to it as expected. But then the Data Sources window is empty no matter which of the three projects I select.
Clearly I am doing something wrong. The videos all show the ability to see the data source in the "Data Sources" window after setting up this three project structure. One other thing I noted. In most of the pictures in articles showing the Data Sources window. The top most entity in the window is the project file itself. Then in a tree structure you would see the various data sources under that top most entity. When I was able to see something in the data sources window, the top most entity was a data source NOT the project file, with the data sources under it.
Any idea what I am doing wrong? It seems like I need to do SOMETHING to make the data sources in one project visible to the others. And possibly something to make a datasource visible once split apart using the "Dataset Project" property.
I have a datasource linked to a table in a database.When I wnated to display this data on a form, I just dragged the datasource onto the form and it did everything for me, including the code to fill it;
My problem, is that this program will have multiple users, and I don't other users to be able to see each others data. So the problem with the above statement is that it fills the table with ALL the data in the datasource. How can I make it only display data that is for a specific user?Here's the code that is used to fill the tableadapter:
Private Sub frmViewCurrent_Load(ByVal[code].......
What 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.
I'm trying to create a simple Data Grid that will automatically save changes. So far I have a data grid connected to a MS Access 2007 Database that reads the data. I can create new fields in the Data Grid, but I need to program to save the data automatically to the database on update (or on close).
I'm developing a web application that provide a service of online reservation, and I need to save the data (for example in a specific day and access to them).How can I do that.Is it possible using : System.Web.UI.WebControls.Calendar?
I'm working on a project which are generating some data from my VB.NET software and I wish to save those data into sql server. But my concerns is the speed of saving and the large amount of data. For every 0.5s, one set of data will be generated and the process will keep running for about 8 hours, so at the end of 8 hours, roughly there will be 60,000 set of data generated.May i know what is the best option/method of saving the data into the sql server in not hanging up my software and also keeping the pace with the speed of 0.5s data being generated?
- Speed of 0.5s. I have to maintained for every 0.5s, one data must be generated. Cannot delay too much.
- I can afford delay in the sql database, meant the data might not be necessary close to real time.
I have a small application that consist of five tables. The main table is called inventory. I have four tables linked to the Inventory table
[code...]
I can go in and enter data, create a new record and add more data and then click Save - nothing happens. I can cycle through the records and they will show. However when I exit and reenter the program (stop/start debugging) done of my new data is displayed.
I am thinking the problem has to be with the four tables connected to the main table via the ID's. Although a record is not being added to these subtables. So, I am not sure what's going on.
I have provided the code below. Please take a look and give me some direction.