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Hello !
i'm new in vb.net.I have to create a project and i have a question :
i'm thinking to use typed dataset.The database is on another computer in network (sql server 2008).The database has 20-30 tables and will grow not much (10-20 mb on every year)
is true that the dataset keep a full copy of original database on my computer or only the database schema? ( i have read several articles but i don't understand this).is this a performance problem for my situation or no?
Thank you in advance.
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Have a look at this Article, first example for SQL Server ADO.NET code example[^]
As you can see you take as much data as you require for the operation and not the entire database.
Lobster Thermidor aux crevettes with a Mornay sauce, served in a Provençale manner with shallots and aubergines, garnished with truffle pate, brandy and a fried egg on top and Spam - Monty Python Spam Sketch
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dcode25 wrote: is true that the dataset keep a full copy of original database on my computer or
only the database schema?
No. It only holds the data that you retrieve.
Copying an entire database would be very performance prohibitive. What if the DB has 4GB worth of data in it? Or a single table for that matter? How long would it take to copy all that data?
The dataset will hold an internal schema of only the columns that you retrieve. That information is lost when the dataset goes out of scope.
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Thank you !
But why on internet there are many articles that describe the performance problems on typed dataset.i read that typed dataset hold an offline copy of database.Now dataset holds only the schema or with all the data ?
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Neither holds an off-line copy of the database. I have no idea where you got that from.
The typed datasets are there to make it easier for new people to work with databases. Frankly, I find them to be a huge pain since they have such a large overhead and they hide much of the work that goes on with databases.
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if you are storing large amount of Data in DataSet then it will take lot of memory.
DataSet can have the Data as well as the structure and the relation between the data.
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hi
i write a software lock program and want to test it .
please download that and inform me that is good or bad.
can you help me?
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hoorandsoft wrote: i write a software lock program and want to test it .
please download that and inform me that is good or bad.
Probably bad; people on this site generally do not download programs as referred to in questions like this. Also, and more importantly, you have not explained what this program does (locks what?), nor have you posted a link to it.
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I am in need of a open source solution that will manage license keys for my application. I need to have a central server that will keep track of how many installs are done for each key and I need the software to check into the server each time it opens to make sure the key is still valid. Any suggestions?
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Why not write a web service that your application sends the license key to?
you can the record the information that you need and if the license key is invalid then you can terminate the application and tell the users that they need to purchase a license.
Lobster Thermidor aux crevettes with a Mornay sauce, served in a Provençale manner with shallots and aubergines, garnished with truffle pate, brandy and a fried egg on top and Spam - Monty Python Spam Sketch
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<?xml version="1.0" encoding="utf-8"?>
<LicenceManager xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://visionontech.com/vbp/LicenceConfiguration">
<ApplicationName>ovE1c/0l6IoKP/KF6bpqv22zqoYuT3Wv</ApplicationName>
<LicenseType>7Ax330npgHE=</LicenseType>
<VersionType>bbUl/DISjDzJkqERNmGqY8eWlTKz+Er3qSWdcEGFDUdsWo9DJrviULY/entknwWw2Z67rm0RnqeB3ENiAa1blfEkGPtfeELVxVG44JG4J5w=</VersionType>
<CompanyName>KWZwGJLdl+pI240K/PURWg==</CompanyName>
<SerialNumber>7515b594-6afb-4f0f-bf4c-13351339191c</SerialNumber>
<MachineID>I50NMYu1RZix+7AuMOhIDyhyFkiepjdK1Sy93luDdi4nCxRLW+Yy259FgXAvKvX9</MachineID>
<Signature>9XvKvAXgF952yY+WLRxCn4idDul39yS1KdjpeikFyhyDIhOMuA7+xiZR1uYMN05I</Signature>
<City>Q6H8NNOnO80=</City>
<CreatedBy>TZdhgIlUIBo2BIm8yvL3ww==</CreatedBy>
<LicenseCreationDate>1xtf7PZmvZQ5e+ohObsHFHokaELQyvIq</LicenseCreationDate>
</LicenceManager>
my laptop licence is
i m using other computer d'not work plz help me brack my code
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We have no idea what you're talking about.
If you want someone to CRACK (not brack) your license, don't even bother asking.
You come to a place where people make their living by writing and code ask us to crack something, effectively stealing someone code that they put a lot of time into writing. You're an idiot.
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please kindly help me on how to connect to ACCESS database using a ODBE DSN on another computer with VB6.0. Thank you and God bless u.
please kindly help me on how to connect to ACCESS database using a ODBE DSN on another computer with VB6.0. Thank you and God bless u.
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ConnectionStrings.com[^]
Why are you even using a DSN?? All it is is a connection string in text file...
BTW, that's ODBC, not ODBE. And I highly suggest using OleDb instead.
Since Access is a file-based database, you have to have a path to where the file is located. That'll be a fully qualified path starting with a drive letter (network mapped drive) or a UNC path (\\server\share\...).
And for the love of ______, please stop using VB6 and move to VB.NET. VB6 has been dead for quite some time now.
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Hello !
Please tell me how can I scroll a panel without a scrollbar or make scrollbar invisible
Panel_coord_x.AutoScroll = True
Panel_coord_x.VerticalScroll.Visible = False
Panel_coord_x.VerticalScroll.Enabled = False
Panel_coord_x.HorizontalScroll.Visible = False
Panel_coord_x.HorizontalScroll.Enabled = False
the above code not working.
In my form I have a main scrollable panel and 2 small panels representing the screen coorinates. When I scroll the main panel,the other 2 panel must scroll also :
If (e.ScrollOrientation = ScrollOrientation.VerticalScroll) Then
Panel1.VerticalScroll.Value = e.NewValue
Panel_coord_y.VerticalScroll.Value = e.NewValue
Else
Panel1.HorizontalScroll.Value = e.NewValue
Panel_coord_x.HorizontalScroll.Value = e.NewValue
End If
This is working fine except : I can't hide the vertical and the horizontal scroll bars for the second 2 panels.
Panel_coord_x.HorizontalScroll.Visible = False
and
Panel_coord_x.AutoScrollMinSize = New Size(0, 0)
does nothing.
Thank You !
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None of that is going to work because if you Make the scrollbars Visible=False, you turn them off.
You would have to put a Panel control inside another Panel control then change the Location of the inner Panel control to scroll the content up and down. Setting the Vertical and Horizontal scroll values will do you no good because you don't have any scroll bars.
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That's how I do it.
I've also had occasion to use touch screens, and use the same panel trick. When it fires a mouse-down event, we track the starting position. If you move your finger past a certain distance from the start point, it scrolls the panel. If you don't pass the threshold, the button gets the mouse-up event fired. It works pretty well, and is good in a distribution environment.
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Hello!
I am trying to make a 2D map editor for my game.
My map is based on a grid 48x48 pixels and 3000 cells(1 cell=48x48pixels).
To do my editor I created a PictureBox array on a scrollable form.
Here is my code for the array :
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Me.AutoScroll = True
Dim rows, columns As Integer
rows = 0
columns = 0
For i As Integer = 0 To 3000
Dim my_picture As New PictureBox
my_picture.Parent = Me
my_picture.Size = New Size(48, 48)
my_picture.Top = CType((rows) * 49, Integer)
my_picture.Left = CType((columns) * 49, Integer)
my_picture.Image = My.Resources.board
my_picture.Visible = True
columns = columns + 1
If columns = 60 Then
rows = rows + 1
columns = 0
End If
Next
End Sub
Each of my image have 5 events :
Mouse Click
Mouse Enter
Mouse Leave
Mouse Move
Mouse Hover
Everything is working fine but to load the form for the first time takes about 30 seconds on a I7 PC with 8 GB DDR3 working on Win7x64 bits.
Can you tell me what to do to take less time to load all 3000 cells ?!
Thank You !
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You should never use hundreds of Controls on a single Form, Controls are expensive and slow, as you discovered.
If you are considering a matrix/grid of Controls, rethink your design, and go for a single Control that behaves like a 2D collection of smaller ones: a single Panel could be made to paint 3000 smaller images, its Click handler could decide which cell got clicked and fire an event in the right cell, etc. Yes it will take a bit more code, but then it will behave as it should. In summary define a Cell class that isn't a Control, all it does is (a) implement its business logic, and (b) tell your overall Control the GUI parameters (mostly position and rendering info).
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Can you point me to a sample please ?
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Unfortunately I don't have one around.
I looked at some of the board game articles here on CP:
- for the smaller boards (chess, reversi), they tend to use a Control for each cell (hence 64, acceptable).
- Hexomania - A Game for Hexagons[^] doesn't use a Control per cell for obvious reasons, however it doesn't have a Cell class either.
- My Sokoban article[^] (the only game I published about) has a single Panel (see file Board.cs), however it doesn't use a Cell class, it has a number of objects that move around; and it doesn't use the mouse at all, it is keyboard driven.
I suggest you look around some more, there's bound to be a good example in there somewhere.
BTW: when most examples seem to be in C#, that is not really relevant; the same concepts would apply no matter what language you use.
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I have created a windows service (in VB, using VS 2010) and once I have it installed and attempt to run it, I receive the following error in the event viewer:
Service cannot be started. System.InvalidOperationException: Cannot change service name when the service is running.
at System.ServiceProcess.ServiceBase.set_ServiceName(String value)
at PostProcessing.PostProcessing.InitializeComponent()
at PostProcessing.PostProcessing.OnStart(String[] args)
at System.ServiceProcess.ServiceBase.ServiceQueuedMainCallback(Object state)
I have a feeling that this has to do with the installer, but not sure what to check. All of the names are "PostProcessing". Anybody have an idea for me? Thanks.
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OK, looking the stack trace, in your OnStart handler, you're calling an InitializeComponent method. You normally don't see that in a service at all, but you do in Windows Forms apps. Makes me wonder what you're doing...
From the InitializeComponent method, you're doing something with a ServiceBase object. Perhaps you inherited that in a class of yours??
Perhaps you're setting a Name property somewhere you shouldn't be??
It's easy enough to trace. Put a Thread.Sleep in your OnStart method for, say, 20 seconds. Then set a breakpoint on a line just after the Sleep. Start the service, then go to Visual Studio and in the Debug menu -> Attach to Process... Find your service and attach to it. When you hit the breakpoint, you can step through the code line-by-line and watch what happens.
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Your reply made the error make sense.  Esp. the "InitializeComponent" piece. I wanted to use a windows service so that I could use the timer to schedule it rather than schedule a task to run as a user. I have moved the project to a windows form, and will use a service to run the program instead. Most likely what I want to do would not work as a service anyways...
My objective: Multiple transactions against a remote server, sending and receiving JSON, deserializing the responses and then taking the appropriate actions on a MS SQL server db.
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