[VB 2010] Destroying Objects And Retaining Application?
May 22, 2012
I have written a program to add a timestamp to a data sheet which had the time in seconds at which a sample was taken. The sampling was done every 0.1 seconds i.e 10 Hz sampling rate.The code I wrote enables one to select a file to which the time stamp must be added, and then runs a macro from excel when you click "Add Timestamp".
I am having a problem destroying the objects though so that they don't end up hanging around in the background. If Excel is already open I do not want it to close at the end of the program, I want Excel to simply return to its state before the application was run in order to prevent losing data on another unrelated excel task which may be open. The macro which is called closes any sheets which it opens. The other problem I am having is that if the program encounters an error there are a number of Excel objects floating in the background. My code is posted below.
Imports Microsoft.Office.Interop.Excel
Imports System.Runtime.InteropServices
Public Class Form1
I'm developing an interface for users that will allow them to enter data into a database without having to know SQL. Problem is, some one out there probably does.
How can I stop them from deleting/screwing with my data when they're typing entries within my text boxes?
For example, I don't want anyone to be able to type in DELETE * or any other kind of SQL statements in a text box to ruin the DBA's day.-Nothing to see. Move along.
I've almost finished my database application, and I had an idea to insert a button that creates a copy of the database. However, when I click the button, it destroys all of the data in the file before copying. It's a 2000 .mdb Access file with 500+ rows so far.
Here's the code that handles the backup: Private Sub btnBackup_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnBackup.Click
disposing http listening object when program closed which located other file than my main form.I am starting http listener like this :
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load WebServer.Main() Klasör = "C:UsersSalihDesktopWebServerWebServerWebServerinDebugWWWRoot" Sayfa = "index.html" End Sub
There is a check box in my webform. whenever i tick it ..and click on back button it will not retain its state ..when i comeback using the next button to the same page.Note: view state is enabled in the control There is no code in the page load event
Code below: Protected Sub chkBx_SR_wu_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) Handles chkBx_SR_wu.SelectedIndexChanged
Why a public variable is not retaining it's value when exiting a subroutine.
I want to search through an array and if a condition is hit then the subroutine exited (thereby holding the index value of a variable named MarkerNo)[code]...
I have a datalist control that is not retaining it values during postback when the control causing the postback is outside of the update panel that the Datalist resides in. I have verified that viewstate is on for that usercontrol as well as all its parent controls. My basic situation is that I have a Datalist that contains a user control on a page. When the user selects several rows in a grid and presses a button, a datatable is filled on the backend and assigned to the Datalist which has its item template set to the UserControl.
On ItemDataBound I set specific properties in the control which customize the messages on that control to the specific item. This is then popped up using the AJAX Control Toolkit Modal Popup[ Extender. When the user presses Save the whole page posts back. Data is collected from the user controls and saved to the DB and the popup disappears. The issue I am currently having is that the DataList has 0 items when the save button is pressed instead of the appropriate number. THis issue just started appearing after we upgraded from .NET 2.0 to .NET 3.5.
Throughout our program, forms are opened like this[code]...
The problem is that when forms are closed, they seem to not really be closed, only hidden - if I add some text to a textbox and close/reopen the form, the text is still there, rather than the textbox being cleared like normal. This is presumably because the form always uses the same instance.
Is there any easy way to fix this other than going through the entire program and creating a new form instance for every ShowDialog() call (there are hundreds)?
I can't remember very well the instances where my selected items has disappeared as if I did a "Reset ToolBox", the last time I remember was when I installed the Service Pack early this year. But last year I think it has been reset frequently and I find it bothersome to reselect all those items again and again.Is there any configuration that I could set so that my selected items are safeguarded, that is they won't be removed no matter what?
I have an application which is grouped in a MainApplication and serveral Modules (DLL's) The Main Application is basicly a Form with a NavigationBar on the Left Side (like in Outlook 2003) and an MDI-Parent. There is also a Simple Login Routine on this Form. I store the UserName after Loggingn to a Property. The DLL's holds functionallity and Forms for various Sections for example there is a Employee.dll which holds functions and a form to show all Employees.
On Loading of the Main Application I loop trough all dll's in a "Module"-Folder and extract NavigationItems from them which I add to the MainForms NavigationPanel. I don't have a reference to the Modules because I want to make it as flexible as possible so that it is possible to delete a Dll form the Module directory in order to remove the functionality from the MainApplication. The Modules could work also without the MainApplication if they are Complied as an exe insted of DLL of course. This works fine so far.
I have the following code below in which I have a class with some class level Excel objects defined.When I call excelModule.Test from another class all these Excel objects are getting created and I can see an Excel instance in Task manager.
Do we have unload event for class to release these objects? Module excelModule Public myRange As Excel.Range
point me to the best way to store persistant objects ( of my own class) in a vb application? I am putting together a simple family recipe application and have created a food item class. I would like to store the instances ( food items) indefinately so that they are there each time I start the program complete with all properties and meethods
I sometimes come across patterns or common practices that I do not agree with. I have a clear opinon of what is considered "good design", which is mainly based on my understanding of abstraction and creating layers.IMO, the core of an application is it's object model. It's a hierarchic model where one object references other objects or lists of them. That's a memory-internal model. For example, a house object references a list of rooms referencing lists of furniture.An object is identified by it's reference. There are no IDs or PKs in that layer.Saving/Loading data is an additional feature. Sure, no application will do without, but it's based on top of the core of the application. I could write an application that works very well without loading/saving, and for version 2 I will think about whether to save data to a database or an XML file. Merely this fact proves that a database layer is not the lowest. I've never agreed with that three-tier model - even if you call me unteachable.
In addition to all application objects, there are Datasets - and that's my problem now. They can be considered as a copy of what is already present in the application's object model. Its from a different, table-oriented view. As both structures exist in parallel, there's the need to synchronize the DataSet with the (rest of the) application's objects.That's the task that I am always struggling with, and I ask how you handle it. I know this is a major design question but, fortunatelly, I could quite get around this problem so far.The only solution I can imagine is maintaining additional relation lists. For example, whenever the property of a room object changes, that change must be reflected in the associated DataRow in the DataSet. For this purpose, I need a look-up table that tells me the PK of the given room in the database. It requires a lot of additional efforst to do all the synchronization.Again, the house or room object itself does not have a PK and it won't get one because on that layer, it doesn't even know that a database exists.
I have a structure with 6 arrays inside it that is serializable so I can save the arraylist of them to a file and load them from the file. This part works.
When loaded from the file the data from a single specific record is populated to a listview control, this works on form load. The user can then select different records and in theory display the data in them (specifically the stuff in the arrays).
Displaying the data works as I'm editing the data, and on first load of the form and displaying the "default" record from the structures. Any other time (trying to switch between records during editing or after loading) the record is pulled (as shown by stepping through the code line by line) but the data in the arrays in the structure and only the data in the arrays is missing.
I've gone through all the code that runs and there is nothing that overwrites the array data in the records between displays so I'm at a complete loss as to why this data is going missing.
Below is the structure and the code.
Defined in a Module so as to be accessible when needed in several places through the program:
Public JBonus As New JobBonuses Public JBonuslist As New ArrayList
On load to set dimensions to the arrays:
JBonus.Str = New Integer(999) {} JBonus.Agi = New Integer(999) {} JBonus.Vit = New Integer(999) {}
I have a project in VB.NET which is working fine which essentially has a Datagrid that has a TemplateColumn included which is a column of Checkboxes. The code to declare the datagrid is here...
everything you see sbove is working perfectly fine...in the sense that when I click one of the checkboxes, the page_load fires, the gridItemDataBound fires on DataBind() and when all is done, the checkbox retains the value that the user clicked the checkbox.
With all this exact same code converted to C#....the events all fire in the same order, but the checkbox selected value always clears...
how I can make a progress bar change colors while retaining the look of a Windows 7 Progress Bar. What I mean is, default it show the green. However, setting backcolor and forecolor does not affect the progress bar while XP styles is enabled.
What I am trying to do is make the progress bar the red progress bar if an error is encountered. I have the error solution set up, I just need it where the progress bar turns to red if the event of the download is stopped by internet connection being disconnected.
Visual Basic for Applications (VBA) Information Visual Basic for Applications (VBA) MSDN Forum Convert C# to VB.Net
How do I effectively declare a Global Array which I can access the values of that array from any procedure? I have a Userform from which I will call various sub procedures depending on the actions performed on the useform. I have one procedure (Procedure1) where I have set up a multidimensional array and input values to it. I have another procedure (Prodedure2) where I want to access the values in the array - I DO NOT want to pass the array values directly from Procedure1 to Procedure2.
I am populating a Checkedlistbox "lstExpert" from table "TableA" succesfully. Whenever an item is checked in the Checkedlistbox "lstExpert", i am saving it into another table "GroupExpert".
[code...]
Is it the right way to do by comparing index in Checkedlistbox "lstExpert" and "Listbox1" Is there a way to bind it directly to the table "GroupExpert" meaning if the value of the Checkedlistbox "lstExpert" is present in the "GroupExpert" then the item will be cheked... I tried the following code and nothing seems to work.[code...]
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Dim StreamReader1 As New IO.StreamReader("L:\Glossary\Glossary.txt")
I have a DataGridView bound to a binding source. I have also, however, added an unbound column in which I plan on putting numbers calculated from the bound columns. The problem is, Any time I edit my unbound column (on any row), the value doesn't stay. If I programmatically edit the values, they never show up. If I type in the cell, then upon hitting enter or clicking outside of the cell, whatever I typed disappears.
I have a windows forms application built in VS2005 and migrated to VS2008 that I "inherited" that occasionally will not show some of the objects (i.e. a button or something) when a user runs it. This is sporadic and does not seem to have any notable pattern.Are there any specific types of things I should be looking for that might cause such behavior? I tried looking at available memory and hard disk space issues and that did not seem to have any bearing on the problem.
I have an application that use in it the 'Interop.ShockwaveFlashObjects' assembly when bebugging everything works smoothly but when i publish the application all the Shockwave objects are not shown ????...what am i missing
I created this function to remove vbCrLf from the values of properties in a Custom Class:(vTransaction)
Public Function ValidateTransaction(ByRef vTransaction) Dim property1 As String Dim value1 As String For Each p As System.Reflection.PropertyInfo In vTransaction.GetType().GetProperties() If p.CanRead Then
[Code]...
Throughout testing I can verify that vbCrLf is being replaced with a space as expected. When I re-examine vTransaction the changes have not been retained and the vbCrlf's are still there. What do I need to do to retain the changes being made to values in vTransaction.
I am developing a COM Add-in using VB.NET in Visual Studio 2008 Pro for Outlook 2003 and am having trouble assigning images to custom toolbar buttons. In a nutshell, I am having to convert from an Icon type to a stdole.IPictureDisp type so that I can assign my buttons a picture. The picture displays, but it loses the Alpha channel and the background is no longer transparent. I can verify that before the conversion to IPictureDisp object, that the PixelFormat property is set to Format32bppArgb (2498570). I am using a coding technique suggested here:[URL]. For C# users, this link [URL] shows how to modify the IPictureDisp one pixel at a time and rebuild the transparency, but I can't find similar functions in VB.NET...
I'm trying to program a personal project, but I've hit a bit of a bump in the road.I've got a Button, a Textbox, and a CheckedListBox; when the button is pressed, whatever is in the TextBox is added to the CheckedListBox. However, when the form is closed and reopened, all of the CheckedListBox's items are no longer present. My CheckedListBox's name in the code is ZapList.
Can someone assist me in, not only saving all of the CheckedListBox's items, but retaining whether or not they were checked as well as the order they were in? I've run out of hair to pull (figuratively) and I really don't want to quit this project, too much effort has gone into it and I'd hate to see it go unfinished like my numerous other projects. :icon_cry:
I'm trying to learn Crystal Reports (VS 2005, VB) and per this question I was trying to drive the report with my own data objects instead of through a DB connection.
I found this tutorial and it looked promising as an answer to my question, but after diving in it only seems to apply to web development.
Am I out of luck in trying to power a Crystal Report with .NET objects in a standalone application?
