VS 2010 Have Multiple Object Instances Made At Once?
Jun 23, 2010Like 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.
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'm working on a program that uses a COM Object exposed by a .dll. The .dll has a known bug, though, where it acts very erratically when more than one instance of the object is created under one .dll, resulting in crashes or corrupted data a large part of the time. I'm curious if there is some way I can load another instance of the .dll itself, then create another instance of the object without having to need a new process for every instance.
View 9 RepliesI 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.
I'm creating a twitter account manager using the Twitter API. I have multiple accounts, over 10 of them. I want to automate all 10 of these accounts to do certain things, now the way I started to code the program was so that it would accommodate only one account, and all the codes worked perfectly and were managed by individual timers for individual processes that I wanted done. i could tweet between certain intervals, follow people who tweet certain things without me being on top of it.
Now the problem is that I've been trying to create new instances of subs that I've already created so that I dont have to create 10 new subs with the exact same procedures. I'm pretty sure it's impossible to create copies of subs dynamically or within a loop but it didn't stop me from trying. So question is how can I edit a program that was designed to accommodate and automate only one account, to potentially accommodate over a 100? I don't need codes or anything I need ideas so I can try them, but right now I'm completely blank.
txtSubject1Info.SelectionStart = txtSubject1Info.Find("Hey!")
I am finding specific words in the RichTextBox (in this case, "Hey!") and selecting them by getting their initial position through the "Find" command. Unfortunately, this does not work when I have multiple instances of "Hey!" in the RichTextBox. Here's an example:
Text in RichTextBox:
Hey! This is cool!
The Find command would return a value of 0 in this case. However, let's take a look at another scenario:
Text in RichTextBox:
In this case, the Find command would return a value of 0 again, but I want it to get the initial position of the second "Hey!" statement. I'm wondering how I can do this.
I am using a message queue successfully as I am testing while I am writing a new program. (This is my first time using a message queue.) I have to have multiple instances of my program running, so I was wondering if this would be a problem with the queue? I have tested it and it looks fine, but I didn't know if it is by coincidence, or if the queues were separate.
View 6 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 RepliesIs it possible to look for all current instances of a specified object without specifically IDing each instance as it's created?
View 12 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..
Any best method of managing multiple SQL connections .net (VB). My application connects to four instances of SQL Server (2000, 2005, 2008, 2008R2) restoring databases, modifying data and taking backups. In addition to managing databases the app also has its own DB (on the 2008 instance) for storing various data. I'm using two methods to connect to the instances, SMO (For backups, restoring and retrieving information about the databases, size etc) and SqlClient for querying each database for many tasks such as updating fields and executing sql scripts.I have multiple forms for performing various tasks so there are many places I'm opening / closing connections.
Would it be best to maintain a persistent global connection to each instance from the application? (Two in total, one for SMO and the other for SqlClient) or open close a connection for each task I'm performing?) I'm not using LINK as I need the tasks to be as fast as possible. The connection string will differ on each connection (Based on Instance and Database being connected to) how would I manage this? A string in the config file for the applications database would make sense, as that would be static but the databases being worked on will vary with each connection. Currently I'm creating a connection for each instance within the main form:
Dim 2000Connection = New SqlConnection("Data Source=" & SQLServerName & _
"SQL2000;Initial Catalog=Master;User ID=sa;Password=P@ssw0rd;Pooling=True;")
Dim 2005Connection = New SqlConnection("Data Source=" & SQLServerName & _
"SQL2005;Initial Catalog=Master;User ID=sa;Password=P@ssw0rd;Pooling=True;")
Dim 2008Connection = New SqlConnection("Data Source=" & SQLServerName & _
"SQL2008;Initial Catalog=Master;User ID=sa;Password=P@ssw0rd;Pooling=True;")
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If I create a console application for example with a class named "Person" I can create an object variable with a ceratin name only once. For example:
Module
Module1
Sub
[Code]....
I have the following problem. (VB.Net 2008)I have created a class (myFirstClass). In this class there are a lot of calculations being made wich gets fired by events in that same class.Now i want that same class to be able to fire more instances of itself. However i noticed that each time i fire an event from a Sub the program waits till the event is finished before going to the next line of code. This is a problem since i want the event wich fires a new instance of the class to fire it and forget about it.
View 7 RepliesI have two forms in my application. Form 1 is a listview that is populated with unique Customer IDs. When the user double click the listview on the particular Customer ID then it loads Form2. Form2 has many listviews within it such as a listview for the Customer telephone, another listview for their addresses etc and all the data presented in Form2 listviews are based on the Customer ID that the user clicked in Form1.
So here is my question...I want the user to be able to open Form2 with that particular details of the customer but also to go back to Form1 and double click another Customer ID and opens Form2 again (such as replicating Form2) with the other Customer details.So the moral of the story is i want the user to be able to have many instances of Form2 open each time they wish to view a different Customer ID without having to close Form2 down every time.
My ultimate goal is to get a list of PIDs and have a user select 1 of them.For example: the process image name is program.exe. The application name varies for each instance the program.exe is run, and therefor each application name has its own PID associated with it. By application name I mean the Task name under the Applications tab of Windows Task Manager. Another issue I face is that some systems run x64, so the name is no longer program.exe but program.exe*32
So my issue is, how do I search for program.exe, or on x64 platforms program.exe*32, and if there are multiple instances of program.exe/program.exe*32 running, how can I get a list of PIDs for each and associated them with the application name as the Task name under the Applications tab of Windows Task Manager.that might sound a bit confusing! So if it is, please let me know and I will try to explain more. Any reference guides or example code would be greatly appriciated as I have only used the "System.Diagnostics" but once.
I have made a program with 2 files, say (file1 and file2). Here I need to make an object of file2 in file1 where I need help from file2. And file2 needs the display text from file1 again to execute the enquiry. So I made an object of file1 in file2 to get the content in display text. But I get stack overflow exception when compiling. I do somehow understand why I get this information. But how do I solve this problem. I thought if I made this display variable to be public, I might reach it from file2. But I couldn't get the content.
View 4 Repliesthis 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
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I have a control which consists of a couple of labels and a couple of buttons side by side.I want to add multiple instances of this control to a panel.The problem I have is with positioning/formatting.Whenever I add the control it just gets added on top of the previous one.Should I be using something other then a panel? Are there any tips ot tricks I should be aware of ?
View 3 RepliesHow can I check for multiple instances of my visual basic application? When the user runs the application, I want to know how many instances are already open.
View 2 RepliesI have an application which the user can open multiple instances on the same machine. However, a section of the app would have sync problems if more than 1 instance has control over it. This is where I thought of transferring control, or sharing, between them. What should I be looking into?
They would have to be able to identify which one of them has control and to send text information over. I thought IPC or Named Pipes could do the trick, but I'm unfamiliar with them and examples seem to indicate only a single server will work. Here, I have multiple instances of the same app and every one of them needs to be able to listen for that request for control.
I have a form (form1) and I havea button on form1 (button1) that will start a second form (form2).How can I make it create multiple instances of form2 when button1 is clicked?i tried a process module that the studio comes as standard but it does not allow me to start multiple instances...how can i do this?
View 14 RepliesI have created an alarm program but am having an issue creating multiple alarms. Here is what I have so far. I have created an array to hold multiple instances(10) of alarms that I want to run concurrently.
Code:
Dim SetAlarms(7, 9) As String
Public Shared x As Integer = AlarmNumb
'X=alarmnumb
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What I cannot figure out is how to get the program to read the array and recognize each row as a separate alarm to process. This means it must read the array, know which variables to populate with what information and cycle thru the list.
I have a sub that runs on a button click which I want to create a new instance of a custom class and add it to a list of already created instances of this class. I want the result to be a List Of collection of all of my class instances.
My problem is that each time I run the sub, it simply 'overwrites' the first instance of the class and adds a copy of it to the list instead of writing a new instance. My code is along these lines
dim objFixture as new clsFixture
For n As Integer = 1 To intNoOfChannels
objFixture.SetChannelAddress(n, intCurrentChannelTotal + 1)
intCurrentChannelTotal += 1
next
lstFixtures.Add(objFixture)
Testing a configuration of a Windows 7 workstation acting as a "server" and a Windows XP workstation acting as a "client" (also fails in the same way using a Windows 7 client workstation).
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Good Day. Kinda banging my head against the wall on this one. I have a Mdi application with the start form(mdiparent) and form1(mdichild). On the start form, there is a textbox and a button. Heres how I want it to work:
1. value is entered into textbox and button is clicked
2. if form1 is open with that value, Bring it to the front if not, create a new instance of form1
If Not IsNothing(frmForm) Then 'If it is something
If Not frmForm.IsDisposed Then 'it's not disposed
'loop through the open form1s and compare the form1s property to the startform textbox
'if its the same, bring the form1 to the front
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I am writing an application whose main purpose will be to collect user-entered data on a prescribed time interval (to be used by a dr. during anesthesia to collect patient vitals during surgery). I am attempting to accomplish this by having a form opened from the main window on every tick of a timer. The problem, is that if the user is a bit slow in entering the data on the first window, and the timer ticks again before they submit the first form, when the form is reopened (currently by simply using a show() command), the process of opening the form again simply overwrites the original form rather than creating a second instance.What is the best way to open a second (and possibly 3rd, 4th... nth) instance of the same form?
View 4 RepliesI am working on a project where i have a home form which has two buttons for login for employee and administrator.after clicking on button login form will open,but i want as soon as login window opens d previous home form must be closed or hide..also there is link on login page for home,but as soon as user click on home link new instance of home form is opening,hnce i want to stop dis multiple opening of the form.i tried close() and hide() but no use.[code]...
View 2 Repliesneed help please on how to prevent multiple instances of a form at runtime in vb so tha when a user clicks a button to load a form it loads an if the user clicks the same button again whilst the other instance of the form is running it doesnt open a new one but insted sets focus on the currently running form.br2
View 4 RepliesI have a form which displays temperature and humidity data for a device in the field. I have multiple devices. Rather than creating a separate form for each device, obviously it is much better to have a single form that I instantiate, pass data to, and display. The devices are listed in a treeview, and when the user double-clicks the node, I create an instance of the form, pass the device's data to the instance of the form, and display the form. All of this works perfectly. However, I have a challenge: If the form for a particular device is already open, I don't want another one opened when the user double-clicks the node.
However, whenever I place logic in the program to check for the existence of the form and only allow another instance to be created if one doesn't already exist, it prevents me from creating a form instance for any other device that I may wish to view, simultaneously. So, I have a dilemma -- allow the user to display the data for multiple devices, including allowing multiple forms to be open for a single device, OR only allowing one device to be displayed at any given time.
If the application is used with multiple users/instances adding records to the same database, whats the best practice for doing this and not incurring any conflicts with primary keys. Right now my partial solution is to do a tableadapter.fill before adding a new row to retrieve any new records. But this obviously isnt the best practical solution as the likleyhood of a conflict still exists when letting the apllication increment the key.
Whats a "correct" way to do this, any reading or examples would be great for me to learn.