I want to understand a situation; it's related to datatable clear().I have a code that populate a typed datatable from Excel in a separate thread using a backgroundworker. This works well, the table is filled and I can see the data. Now, I want to clear the data from table and restart the import. The operation is ten times slower than the first time. My datatable variable is declared like this:Private dt as new DataTable - not a local variableI want that all subs from class to be able to use the table, that's the reason I declared the table as private. What I want is to be able to create a new instance of dt (or clear allocated memory) - maybe this is the reason for slowdown.
I'm trying to clear a DataTable and repopulate it, and the DataTable is bound to a DataGridView. Here's the code I'm executing:
vb.net Using reader As MySqlDataReader = myCommand.ExecuteReader SyncLock tableLock running.Clear()
[Code]...
If you want to replace this standard messagebox, handle the DataError-expection When debugging, there is no break in the code. The messagebox just pops up without showing me exaclty where the error is located.
I have a form with a tabcontrol. The tabcontrol has two pages. The first has a form that the user fills and clicks on a button to store the values on a SQL database. The second has a combobox that is filled on the click event of the button with the values of a field of a database table. I put the filling of the combobox on the button's click event in order to display the new (stored) value. The problem is that if the user repeats the above procedure then the displayed values (in the combobox) are doubled, tripled etc. I tried to clear the datatable that I am creating and filling after assigning its values in the combobox but it doesn't work. [Code]
This code is on the button's click event. But it returns an empty combobox. I can't understand why is doing this as first I am filling the combobox with the values from the datatable and then I clear it. Any suggestions for solving the above problem?
I am filling a datatable and after storing the values I want in two variables I want to clear my datatable or erase it.[code]...
As the above code is in a function (and I am calling this function many times) it causes me problems. The variables id and entitycode store the first values (the first time I run the function) and then it always use them. That's why I want after storing the values in variables to also clear the datatable or even erase it (and rebuild it when I rerun the function).
I am working on a vb.net app for a handheld using Windows CE and I have a few columns of data loaded in a datatable from a text data file. Some of the records can have duplicate Account IDs so I cannot use a primary key. What I want to do is take an Account ID entered and filter on just those records. I need to loop through all records with this Account ID, make updates to any of them and then clear the filter.
how to set a filter on a column based on a given string such as an account number? And loop through these records? Can I modify the records at that time?
In My application, I have an MDI form. From MDI form I open all forms as child forms. I have implemented IDisposable for all large objects like file stream DB connection etc. In the Form_Disposed event I dispose all unmanaged objects. After the child form is closed, all unmanaged objects are disposed but managed objects (controls and form) are not disposed and still in memory. I find it from .Net Memory Profiler ([URL]).
So I have write code to remove all event handlers of all controls and form. Now, When form closed, dispose is called and all event handlers and controls are disposed, but controls and form are still in memory.
In my Zeal to get with the "Dispose" program, I implement a dispose pattern (still learning the ways and means of THAT) wherever it seems to make sense.I THINK I have the basic idea. However, I notice that, while Drawing.Brushes HAVE a Dispose method, when I call it, some sort of instability is created in Visual Studio itself, and i get the dreaded "Visual Studio has encountered an error and needs to close" splash screen, with no useable error information. SHould I assume that one should just NOT call dispose on Brush objects, or is there something I am missing here: [code]
I am using VB.NET (Visual Studio 2008) and thus .Net framework 3.5. I have developed an application which has a MDI form and then has several other forms, most of which are shown using form.showdialog and some set of forms are shown using form.show. Whenenver a form (shown using form.showdialog) was closed (usually by clicking on a button (OK or Cancel)) I wrote code Me.dispose. After careful testing and R&D I figured this caused flickering on the screen. There use to be a flicker on the screen and it looked weird.
I am having problems disposing of a image thats stored in a 'DataGridViewImageColumn' . When i try and delete the image the 1st one works then the 2nd time its used i get a 'System.IO.IOException: The process cannot access the file 'x' because it is being used by another process'. How do i solve this problem? i am disposing of the image before i try and delete it but yet its still not working:
PS - I have searched the forums / google for a suitable answer and cant find one
When i use this code my cursor goes to a point on my screen...Cursor.Position = Me.PointToScreen(New Point(285, 200))But when i use it a several times sometimes the position is slightly different...I can't figure it out why it is different after some time... Can i use the dispose function ?ps my form doesn't change in size and it doesn't move and always stays in the center of the screen.
I was wondering if you should dispose undisposed resources before closing your application. Maybe it's not necessary to do this because closing your application automatically takes care of this.
I have prided myself in having a pretty clean code however in the game I am making I have a player view (showscreen) and a host view, which is a copy of the player view (on a smaller screen). This way the host can see what's going on.The problem is that the graphic doesn't dispose properly and Garbage Collector gets it, though I have noticed it will crash if GC doesn't get it in time. The larger the showscreen window the more junk gets put into memory, which sucks.I thought I had everything correctly disposed below but still doesn't get the job done.
I have a timer that runs every time by itself, and for the code the runs in it I would like to have it clear the dataset before it does anything, the timer runs every 10 seconds, so I tried to do dataset.clear but it would crash if the dataset had no values
With every sheet music file opened, I am also loading background music file, if such exists. If music file doesn't exists, I need to clear the previous one from the sourceURL, otherwise I have wrong music playing with wrong notes. How can I do that?
HTML Sub Play_BackgroundSoundFile() Player.settings.autoStart = False Dim urlpath As String = (Application.StartupPath & "UserMIDILibrary") Dim fname As String = Path.GetFileNameWithoutExtension(pathload) fname = fname & ".mid" [Code] .....
in hyper teriminal when i press "ctrl+L" is to clear terminal screen how to write the code in vb.net? Hyperterminal is connecting to serial comport.when i try this it work and return line on debug
serialport.writeline ("at+cmgl=1")
i try this but not work and it still show some lines on debug
I am having a bit of a problem. I am using to array's to fill a CheckedListBox. This works fine, but when i try to clear the collection of items on the next Button Event, it only seems to add the new items to the old list..[code]
This is a simple program, nothing crazy, just for a VB class. The program just a food ordering form. Each part of the order has a group box, with the type of sandwich, side, beverage, dessert you want selected via a combobox, and toppings selected with checkboxes (the code for the beverages is coded differently and giving me 0 problems, but at the instruction of the teacher who saw beverages giving conflicts with the way everything else was coded because radio buttons are used instead of checks).
I use this to delete cookies System.Diagnostics.Process.Start("rundll32.exe", "InetCpl.cpl,ClearMyTracksByProcess 2") works fine I checked the folder myself it deletes all .txt files.
But here Is the problem lets say I log into hotmail, Clicked the button to Clear my cookies. And navigate to log in page again, It will navigate me straight to inbox just as if I have cookies but the folder doesn't have .txt cookies file. just (index.dat). Is this means we must restart the program to this to take effect? (Works if you restart it) If so, how can I turn off webbrowser1 for a sec and turn it back? or something like that just to make sure it takes effect without me reopening the program.
I am trying to have a DateTime variable which is in a MM/dd/yyyy HH:mm:ss format convert to dd/MM/yyyy HH:mm:ss. I am using VS2008 Pro, and when I create a var:
dim dt as datatime = datetime.now It automatticlly defaults to MM/dd/yyyyy. No matter if I convert, parse, use globalisation or anything... convert to a string, which works with dd/MM/yyyy, but the minute i move it to a DateTime var type it goes back to MM/dd/yyyy I need to use this date/time to insert into a MS SQL Database and the colume is datatime type. But also is part of the app.I do not want this to be a string, I can do that, but I do need it to be a datatime in the correct format (dd/MM/yyyy HH:mm:ss)
