I have made a For next loop with an array. I want all my picture boxes to follow each other within the loop. I have currently been using old code, but not in a loop or array format. The old code works. The array code only makes the 2nd picture box follow the FIRST one. It doesn't loop the rest. I have checked the code and cannot determine any mistakes, else I'm missing out on something I haven't been taught.[code]...
I am writing an app to be a single button failover of a set of mirrored SQL servers. The app has to handle several other functions (enable/disable and start/stop of services, writing to local registry, copying files from server A to server B, initiating stored procedures, etc.)I have a collection of labels that indicate the status of 4 services on 2 servers, I wrote a function to check the services when passed the machine name, and the service name. Originally I just called the function 8 times (4 services, 2 machines) and populated the labels 'manually'. I have all of this within a timer so that the service status is refreshed every couple seconds. Id like to clean up the code to a single for/next loop that operates on 2 arrays (an array of service names, and an array of labels) such as:
'**Fetch_Status is the function that gets service status, it accepts 2 strings, machine name '**and service name and returns status "running", "Stopped", as my_status Dim Services() As String = {"Service1", "Service2", "Service3", etc.}
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The only reason I want the control array is to be able to use the .Text and .BackColor properties of the labels in the loop. If I make an array of strings with the label names it doesnt seem to pick that up.
I am trying to make a collection of controls that I can loop through. So I have this code in my form... Dim WizardFrameCollection As New Control.ControlCollection(Nothing)
I then try to add controls to the collection by I get a error "Object reference not set to an instance of an object." WizardFrameCollection.Add(Me.GroupBox1) I am not sure why I am getting this error. Groupbox1 is a groupbox that is on the form.
Imports db = System.Data Public Class CustomerADO Dim cid As Integer Dim fn, ln, em, pw As String Dim bl As Decimal [Code] ..... What should I do in the while loop to make array of customers objects. And what should be the code in the form to add this array of customers to listbox.
I only started using visual basic earlier this year so I'm still a newbie but I've been wondering some things:
1. When you have a picturebox back color to transparent, objects under it still get hidden. Is there a way around this?
2. I've been trying to make a program where you can control an object, and it has multiple animations, but I can't figure out a way of doing this other than having a bunch of picture boxes together and making them visible/not visible as needed. Is there a better way to do this?
3. (I think) I know how to make global variables (dim whatever as global.system.integer ? I don't have it on the computer I'm posting with), but how do I make another form use them?
4. Is there a way to have multiple sounds play at the same time? Whenever I play a sound it stops whatever else is playing.
I am constructing a program, i am new to Visual Basic, but i have past programming experience. I was wondering if anyone knew how to form a loop that could...lets say calculate the answer when two numbers are added together,and it would repeat this thousands of times, etc. And if there is a way, would it be possible to calculate the time taken to complete this loop.
I didn't think it fair to post a comment on Fredrik Mörk's answer in this 2 year old post, so I thought I'd just ask it as a new question instead..NB: This is not a critiscm of the answer in any way, I'm simply trying to understand this all before delving into memory management / the marshal class.
In that answer, the function GetByteArray allocates memory to each object within the given array, within a loop.Would the GetByteArray function on the aforementioned post have benefited at all from allocating memory for the total size of the provided array:
Dim arrayBufferPtr = Marshal.AllocHGlobal(Marshal.SizeOf(<arrayElement>) * <array>.Count)
I just wonder if allocating the memory, as shown in the answer, causes any kind of fragmentation? Assuming there may be fragmentation, would there be much of an impact to be concerned with? Would allocating the memory in the way I've shown force you to call IntPtr.ToInt## to obtain pointer offsets from the overall allocation pointer, and therefore force you to check the underlying architecture to ensure the correct method is used*1 or is there a better way? (ToInt32/ToInt64 depending on x86/64?)
*1 I read elsewhere that calling the wrong IntPtr.ToInt## will cause overflow exceptions. What I mean by that statement is would I use:
Dim anOffsetPtr As New IntPtr(arrayBufferPtr.ToInt## + (loopIndex * <arrayElementSize>))
I've read through a few articles on the VB.Net Marshal class and memory allocation; listed below, but if you know fo any other good articles I'm all ears![URL]..
A few years ago I have been busy creating this application but it didn't succeed, now Im coming back to it and similar problems occur. Basically I use SetPixel on a given window to draw a line, work fine, but the line goes away as the window redraws itself.The problem: I have been putting timers and threads on it to make sure the line is being drawn. Is there any way to make a loop to make a certain thing happen about 10-30 times without taking in too much memory/CPU?
I am creating a dll with all the functions and subroutines that I use all the time and I decided to create a function that I can pass different types of array to so the function obviously (or not) would have an array of type object. Now I no you can pass any type into an object type but when I pass an integer array into an object array I get an error.
value of type '1-dimensional array of integer' cannot be converted to '1-dimensional array of object' because 'integer' is not a reference type.
Shared Function CompareArray(ByVal FirstArray() As Object, ByVal SecondArray() As Object, Optional ByRef ErrorMessage As String = "") As Boolean Dim IntArrayOne() As Integer = {1,2,3,4,5} Dim IntArrayTwo() As Integer = {1,2,3,5,6} Dim IsSame As Boolean = False IsSame = CompareArray(IntArrayOne(), IntArrayTwo())
I am having some trouble creating an object array of different object types. Here is what I have so far:
Public Sub New() Dim b1 As New Book("Book Title 1", "Gold Book Publisher", 1.0, "Bob Jones", "192DJDJD212", "01/02/10") Dim b2 As New Book("Book Title 2", "Gold Book Publisher", 1.0, "Bob Jones", "192DJDJD212", "01/02/10") Dim b3 As New Book("Book Title 3", "Gold Book Publisher", 1.0, "Bob Jones", "192DJDJD212", "01/02/10")
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If I define the array As Book (Public publicationArray(6) As Book) or Magazine (Public publicationArray(6) As Magazine) I am able to access the properties of that class but not both. I think I need to define a type for each array instance but not sure how to do this.
I have an interface that describes an specialized list in my application...
[Code]....
Is there a way to make an interface serializable, or am I going to have to convert each of my objects into a concrete class implementing the interface, and then return that class?
i have this code in asp.net 2005 page under vb codes on myreader.Read gives me "variable myreader is used before it has been assigned a value a null reference exception" and in the ex msg " object reference not set to an instance of an object".
Ok i need to make an object in this case a picture box draw a line to another picture box with the shortest length while avoiding other type of objects such as labels i am not sure how to do this but so far i have come up with
Private Sub ProgressBar1_ParentChanged(sender As Object, e As System.EventArgs) Handles ProgressBar1.ParentChanged If ProgressBar1.Value = 50 Then
In an application I am working on I have created a product class which represents an inventory item. I have also created an inventory class which represents a collection of product objects.In the constructor of the Inventory class I load 4 products into a product collection. Each product consists of a code, description price and quantity. Within the form load i would like to add a procedure that loads each products code property into a combo box.Obviously I could do this by hard coding the values but I would like to loop through the collection of products and populate the combo box with the codes contained inside the product collection. This is what I am struggling with. Below is the code for my inventory and product class.
Public Class Product Private sCode As String Private sDescription As String
i trying to do login form, if user & password correct, then will show Main Form. First time login is no problem at all, after closed the Main Form, it will back to login form. Problem come when i try to relogin again & show "Object Reference not set to an instance of an object" when try to access the database. Attach my code here:
For some reason, on the line where I try to set the value of the key, I get the following error:
Object reference not set to an instance of an object
vb Private Sub writeToKey(ByVal regValue As String) Dim regkey As RegistryKey = Registry.CurrentUser.OpenSubKey("SoftwareMicrosoftWindows NTCurrentVersionWindowsDevice") regkey.SetValue("Device", regValue, RegistryValueKind.String) 'error occurs here regkey.Close() End Sub
In an application I am working on I have created a product class which represents an inventory item. I have also created an inventory class which represents a collection of product objects. In the constructor of the Inventory class I load 4 products into a product collection. Each product consists of a code, description price and quantity.
Each business object has a matching object that contains sql calls. I'd like to restrict these sql objects in a way where they can only be used by the matching business object. How can this be achieved?
Update Greg brought up the point about testability. Since the SqlObjects will contain very business-process specific sql I don't want them reused in multiple buiness objects. (Basic CRUD operations are all code-generated) Is there a way to make the SqlObjects accessible to only one business object in the business assembly (like yshuditelu and Greg Beech showed) AND expose the SqlObjects to the unit testing assembly?
I'm trying to loop through a collection object in vb2010.The code was originally used in Vb6 The book said that I needed to code a NewEnumerator method first in order to be able to loop through my collection. I coded the following:
[code]...
It gives an error for IUnknown, staging that IUnknown is not accessible in this context because it is a 'Friend'.In the line in the function I removed the Set since it's no longer needed.The error message for this line is '_NewEnum' is not a member of 'Microsoft.VisualBasic.Collection'What are these messages and how do I fix this in VB 2010?m_colCourse is not a system collection.
I got two form. form 1 i ask the user a number of guest form 2 i ask each guest their name, their age i decide to make a loop base on the number of guest but then i got this error. NullReferenceException was unhandled how to solve this...i underline under my code
Private Sub btnBook_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnBook.Click iTest = CInt(txtChildren.Text Do Until (iCounter = iTest) And (bIsNextClicked = True) PassengersDetails(iCounter).ShowDialog() Loop End Sub
i want to see if i can get my hands on a working example of a 2d array something along the lines of continents and 5 sample countries from each continent.i would also like to know how to loop through a 2d array - i know i need a loop inside a loop but cant find any examples.i know to declare a 2d array its like: dim arrayName(,) = {{"sample","sample"}{"sample2","sample2"}}
On the design i have different text boxes that display the prisoner name, birth date, number etc.
I then set all of the the different prisoners up in an array.
I want to know how to loop though this array so that when i start the program up it will start at the beginning of the array with the first prisoners details and then when i click "Next" the next prisoners details will be displayed in all of the boxes.
Whenever I try to create a new CD object I get a stack overflow. I want a parameter to be passed into mediaFactory so that it could be determined what type of media is created. Why I might be having problems with this when I do this "Dim media As CD = New CD()" Public MustInherit Class MediaFactory Inherits MediaContext Implements IMedia Public Sub New(ByVal typeId As Integer) [Code] .....