Scanning Through All Instances Of An Object?
Nov 6, 2009Is it possible to look for all current instances of a specified object without specifically IDing each instance as it's created?
View 12 RepliesIs it possible to look for all current instances of a specified object without specifically IDing each instance as it's created?
View 12 RepliesI'm trying to create 3 instances of the the Workshop selector form for the 3 individuals that I have inthe listbox to appear when I first run the program.
View 4 Repliescan i do some thing like this in .net? and how?
Code:
dim object1 as new clsDatadim object2 as object
object2 = getobject("object1")
"getobject" function is my "needed function"
the purpose is to set object2 to have same memory address with object1 so if i change the properties of object2 then the properties of object1 also changes..
this is probably something I should know, but I'm puzzled by this.I'm trying to create some objects and being able to access and modify these globally. I tried to create a Public Module and declare a few objects in this.I am able to access these from another sub, but I get an exception error when after building and runing the process and trying to modify these object. The same thing happens if I declare the object in the Public Class Form1. For example like this:
Public Class Form1
Public appWord = New Microsoft.Office.Interop.Word.Application
Public wordDoc as Microsoft.Office.Interop.Word.Document
[code]....
I am just getting started with VB.NET - what I couldn't find in my book is whether a new instance of an object with the same variable-name will delete the previously stored values - or will that somehow remain in memory?This is the scenario:
I open a data file and load the contents in 'Dim var As New dataObject'what happens when I again open another file and the same line is encountered:Dim var As New dataObject'
Hope the question is clear p.s. the dataObject is a simple structure with a bunch of variables in it - nothing fancy.
Like i have. Dim MainWindow as new Classic.
But i have another i need to Access.
Is there a Way. Ive Tried and Tried. But i can't find a Way to Load another.
having difficulty with understanding object lifetime / instantiation.I have a windows from with a datagridview and a panel. The datagridview has a checkbox column and a list of names which is populated from a database.The panel has a few text boxes (e.g. name, age, favourite sports team) and a 'save changes' button.
The idea is that when the user selects a person in the datagridview by checking the appropriate checkbox then the panel shows the relevant data for that person (name, age, fav sports team) by pulling the data from a database. If the user would like to update the person's details they can do so by typing in the textboxes and then clicking the 'save changes' button. All quite simple so far.
The way I have designed this is to have a 'panel' class and to create an instance when the user checks a checkbox.(NB - the reason I have created a 'panel' class is that I intend to replicate the datagridview and panel on other tabpages within my form and thought it would be useful to have a generic 'panel' class that I could re-use.)
My code looks a bit like this:
If CheckBoxClicked Then
Dim UpdatePanel As New UpdatePanel(MyForm.NameTextBox, MyForm.AgeTextBox, MyForm.FavSportTeamTextBox, MyForm.SaveButton)
UpdatePanel.GetData()
...
When the user clicks the SaveButton the data is updated to the database and I have a display message (simple textbox) which says "Update successful" and displays for 5 seconds before hiding itself.
Here is the problem:Suppose a user checks a checkbox, reviews the data and does not make any changes, and then checks another checkbox and decides to update the data by clicking the 'save changes' button. What happens is that the "Update successful" message is displayed twice.
I think this is because every time the user checks a checkbox an instance of UpdatePanel is created. If a I select five different people using the checkboxes and then hit 'save changes' I get five "Update successful" messages.
I am not sure how to overcome this. It feels like each time a checkbox is clicked I need to check if an instance of UpdatePanel exists and then destroy it. I tried using UpdatePanel = Nothing and also investigated IDisposable and GC.Collect() but with no luck.
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I am having a problem with a and OOP class i made that contains a sub that creates random integers.
Problem is if i define two instances of this class and configure them(name in this case) then they both display different names but the random integers are ALWAY the same. in this case having the integers the same kinda kills the idea of the program.
Is it possible that the random part only every works for one class, but if .NET is fully OOP then this should not be possible... right?
Some of my Code (broken down to something smaller) i will display for obvious reasons.
Code:
I have a TabControl object on my form with many tabs created in code (TabPages) and my problem is that the same objects that are in the initial TabPage needs to be in the other TabPages created in code, I have this done in code when the user clicks the 'New Tab' menu option, however the same code is used for any new tabs created. The problem created here is that I have an event against one of the objects that appear in the other TabPages, but because the same code is used to create any new tab pages, the event will only work on the newest tab page, if that makes sense? By the way these objects that appear on the other TabPages are properties at the top so events can be handled against them in the respective subroutine.
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I've installed visual studio 2008.is the visual basic in that package known as VB.net? My 2nd question: how can i use scanner for scanning using VB.net?do i have to use WIA? or i can use the default program for scanning?
View 1 RepliesI have been messing around with the scanning packages(WIA and TWAIN) and have gotten WIA to work, but not as intended. At first I used the common dialog to show a Image Aquisition Wizard, but that did not return desired results. Next was twain, but st managed to find was the same C# program over and over and over again, "TwainGUI". A program written by NETMaster on codeproject.What I would like to do is scan from the ADF and save immediately to the users working directory. The problem is I can't get WIA to keep scanning until the ADF is empty.
Psudo Code:
Start:
"Set scan settings"
[code]....
I am ask about the possibility of scanning document (by scanner) from within vb.Net with vb6 I used Kodak image controls(imgscan, imgedit) but with vb.net it seems that they are not working properly.
View 3 RepliesHow I can use scanner to scan an image and put it in PictureBox using VB.NET
View 4 RepliesSo - we are FED UP with our medical records packaging (document imaging) system and want to create a simple filing interface for our scanners to use in VB. Part of this deal is getting VB to interact with a TWAIN Driver.
There is some code out there for ASP.NET and C# - does anyone know of a VB.Net based code I could look at?
I have spent part of my day trying to recreate the ASP into VB but the calls are just different enough to get interesting.
how to program an application that scans the computer in the network in vb.net?
View 3 RepliesI am making an application to scan with TWAIN. I can get to state 4 OK, and scan with the UI. But I need to hide the UI. When I do this the scanner does nothing. I believe it needs some capabilities set (like height and width). So I try to get the physical height and width so I can set them. Herein lies the problem. I get 18874402 back for the physical height and width. (neither can I get the units). I get RC=SUCCESS. I don't think it could be a signed/unsigned issue because what boundary is at 18 million +/- with whatever units? I tried some other code I found but that returns 0. I can't figure out what I am doing wrong. Here's the code:
[Code]...
So I got a request to update specific information on a thumb drive from my program. The idea is that the user does not have to select the drive. If you plug it in and select and option on the program, it will find the drive automatically and update some files for my specific purpose. Is there a way to automatically find a drive in a program?
View 1 RepliesI would like to know if there is a built-in TWAIN Scanning library in .Net 4 to use it in VB.NET.
View 1 RepliesHow can i connect a scanning device to a computer using .net? Code 128.
View 4 RepliesI was just wondering if there is anyway to invoke finger print scanning in a .NET application? (Eg. Windows 7/Vista Login screens - assuming they have the hardware of course).
View 1 RepliesI'm using the LIKE command as in:
If str Like
"*[^s
!-~]*"
Then
Unfortunately, this expression is true for the space character. I don't understand why. I'm trying to determine if str contains any special characters other than the ones indicated by s. If it does, I plan to process the string further.ebassador "Find it, fix it, move on.
I am trying to perform Twain scanning using the twain_32.dll, but no luck. Whatever solutions I have got call the dll GUI.
I want to perform scanning by passing custom settings to the scanner for every scan. For eg. In duplex I want to scan the Front side in color & Back side in Grayscale. OR Scan every Alternate page as Color and B/W
The combination can be anything. I've tried & and succeeded using WIA but it limited me to a certain extent. how to proceed using TWAIN and without displaying the GUI. I am open to options where a communication to Twain Connection Manager is established & commands are passed.
I developed a winform .NET 4 application that has the ability to asyncronous save image from scanner using Bytescout Scan. Anyway I noticed that in some cases (with some scanners) the scanner's GUI opens and then closes immediately after load without performing any scan. Since no error message is raised either from my code and from scanner software itself; is there some settings/tweak somewhere I should pay attention?
View 2 RepliesI'm not really sure where to begin for this. I'd like to scan a specified server directory for all files that it contains in the directory. (I will then compare the sizes to files already existing on the user's machine, but that I've got covered.)
If there's any way I could get around using FTP, I'd be very grateful, as this won't be entirely secure.
I did some exploring of the WebClient and WebRequest classes, but failed to conceive of a way to do this.
I have a multiline text box which is used to enter barcode numbers into. I have a barcode scanner and all the barcodes will end in L2, L3 or L4. Once a barcode is scanned in I need VB to detect either L2, L3 or L4 then go to a new line and repeat. Where I can start to accomplish this?
View 4 RepliesI come straight to the point without going too far. I need to scan all the pixels of a generic image and for each pixel derive the RGB components. I started with the following function that performs its task very good and returns 3 array (R, G, B) with the different values, but unfortunately is too slow.
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Alright well, I'm sort of new to VB.NET.I want to create a scanner that scans websites from lets say google or bing.It then dumps those websites into a list/textbox. It then scans each website for a directory, and if the site says something like "test page", then it dumps THOSE into another list/textbox.
View 1 RepliesIs there any C#/.NET code (or anything that is easily convertible to .NET, such as Java/Python) for virus scanning that is not under the GPL/AGPL ? I found a C# wrapper for ClamAV, but ClamAV is GPL... Something LGPL would already suffice, and as a matter of fact, would be something I prefer. Preferably something in fully managed code, but DllImport is also welcome. COM interop is a no-go, I need it cross-platform (=Windows & Linux).
View 1 RepliesWhere I can find virus scanning/detection algorithms?
View 3 RepliesI am developing an application which will be used to scan the barcode from a particular document, as i am just developing who i will get know that barcode scanning is working i dont have device at the moment
View 2 Replies