I am working on a VB Windows Form and I have a question here about initialize an array (friend variable)[code]But this didn't work and it thrown an exception says Object reference not set to an instance of an object.I am wondering how I can have the array initialized to size 4.
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initialize an indefinite (eg. Decimal) array without setting boundaries on the array length?
View 2 Repliesgiven the following Sub, how would I initialize byte array 'temp'to zeros and give it the length of the incoming byte array passed into the subroutine?
Sub ReceivePacket(ByVal buffer As Byte())
Dim temp() As Byte 'initialize to zeros and length of buffer
temp = buffer.Skip(17).ToArray()
End Sub
I define a arrary.
Dim myStr(100) as string.
Then the length of this array is still 0. Then is risky to cross the bound. So how to intialize this array without using a loop?
is there a shorter way to create an array of 215 boolean 'true's than the following?
Dim ArrayOfBits As Boolean() = {True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True,
[code]....
Assuming the array has 216 elements:
Dim Data As Integer() = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
[code].....
In C#, I can declare an array variable like this: object[] Parameters;
And initialize it like this: Parameters = new object[20];
In VB, declaring and initializing an array is easy:
Dim Parameters(19) As Object
Dim Parameters As Object(19) ' Alternative Syntax
How would I initialize an array variable that has already been declared in VB.NET? Parameters = New Object(19) doesn't work.
For example, how would I translate the following to vb.net?
int value = 20;
object[] Parameters;
if (value > 10)
{
Parameters = new Object[20];
}
[URl] The code in question is specifically at line 143. Whenever I try to access a label in the array like so Dicelbls(0).Text I get a null reference error. Obviously I am not declaring the array right?
View 3 RepliesHow create a array of objects (another class) in VB.NET and initialise it. Since I am not sure about the length of the array, it should be generic. I mean I should be able to add any number of objects to the array.
View 2 RepliesI need some constant arrays to be ported like this one:
[3] - first dimension
[2] - dimensions in each first dimension
[3] size of string array is needed in the language i'm porting from, y - 0, o - 1, \0 - 2 = 3 new RevTable[3][2][3] =
[Code]...
how do i declare jagged array? it has 7 elements consisting of 2 to 8 elements consisting of 3 elements.[Code]
View 1 RepliesIm in a programming class and im having trouble with two problems.
Problem 1.
1. Declare an array of data type Integer with size 10
2. use a for loop to initialize the array with 1, 2 or 3 using given random number function below
3. display content using msgbox.
'paramaters
'low - the lower bounds of range
'high - the upper bounds of range
'returns
[Code].....
I am trying to initialize a multidimensional array. Here is my syntax; this does not create errors but it does not store all values either. Although it correctly prints out all records in this snippet,
dFirstWeek = CDate(FirstWeek)
dFirstWeek = DateAdd(DateInterval.WeekOfYear, -1, dFirstWeek)
Dim dFirstDay As Date
Dim arrWeekYear(5000, 1) As Date
Dim i As Integer = 0
Dim j As Integer = 0
[Code] .....
But this time, only one "j" record appears per "i" record. Why is this? And then after these few records, many dates resembling null dates appear: "1/1/0001". So why do all records appear in upper section, but not from lower? Did I insert values wrongly into this array? And it does not have to have fixed number of rows, just a fixed number of columns.
How to define ,dynamically initialize and print 3D array in vb.net ?
I have this code that return a 3d array and I have errors telling me the there is an argument out of range [code]...
How to get values for array elements in VB.nET from the user.also i wanted to display these values in the combo box.[this is easy i could manage this].
View 2 Replieshow should i initialize the string array in this procedure call
vb
Private Sub SetAddres(Optional ByVal Addrvalues(4) As String ) End Sub
how to initialize it with values and also with empty strings or null values
I can't make difference between public class and private class and friend and protected friend class.
View 1 RepliesI am trying to create and initialize an array of structures of a fixed size. Each struct will be populated when a button is clicked. Here is an example of my struct:
public structure buttonStruct
dim x() as Boolean
dim y() as Boolean
[code]....
In my form_load function I am declaring the array of structs and:
Dim BtnStruct(15) As ButtonStruct
BtnStruct(0).Initialize()
[code]....
Whenever a specific button is clicked, I am trying to collect data and store it in the respective struct and so for example, if button 1 is clicked then I will store the data associated with button 1 into BtnStruct(0). The position of the button is stored in a public variable called BtnNum. If I attempt to store information in the struct inside another function as follows, I receive an error
BtnStruct(BtnNum).x(pos - 1) = temp "btnstruct is not declared. it may not be inaccessible due to its protection level"
How to initialize a multidimensional array by loop operation in VB .Net?
I have some arrays called 'Room', 'Subject', and 'Population'.[code]....
I've been reading about access modifiers in VB.Net lately, and there is something that I can't really understand: How do elements in a Class (or Module) inherit the modifiers of their enclosing block?For example, suppose you have a Friend class Bla in an assembly, with a public method Foo:
Friend Class Bla
Public Sub Foo
(...)
End Class
Does it behave differently than when Foo is set to Friend?
Friend Class Bla
Friend Sub Foo
(...)
End Class
In java I use the Desktop application as under;Create JFrame Add JdesktopPane and in the Jframe constructor intilize the all the child forms and then in the events i use child form.visible method.But in the VB where is best technoque to use child forms to initilize?i also need a piece of code for the application to learn how effectively i use the VB to develop MDI application.
View 1 RepliesWith making the buttons on a form for distance calculating, I need to use a list box but I am confused and a beginner.
I have started the form and made a list box, but I am unsure how to make the results viewable when the program is complete.
i have my main child form open. then i show the new form:
[Code]...
but when the form opens it flickers a lot. so i want move the new form behind the main form while it loads so the user does not see the flicker. once it is done loading i will set the form to topmost. how do i move the new form behind the main form?
Load , Initialize , Activate . What's the difference among them ? Up to now I was used to the classic VB6 events , but it seems that in .NET they are different . I was used to these ones :Load / Initialize : both the first step before showing a form . One appeared in VB6 , the other in VBA .Activate : triggered when a form is selected .However I thing that now , not only they differ , but they also come in a different order ...
View 34 RepliesI have a tool window that I want to stay above the main application form, but not stay on top of all windows forms. Similar to the floating properties window for visual studio - it always stays on top of the main VS window, but if I select another program, like internet explorer, the floating properties window will be behind internet explorer.
What I have is an application that has several forms that may be displayed at the same time. I have a Messages form that displays messages generated by the code in the form, that gives the status of the application. Obviously, the user would not normally be working on this form, but they may want it to be visible to see the status messages from the program (File saved confirmations, etc). So, my two options right now are I can set the form to be on top of all other windows forms or, when the user clicks on the main application form, the messages form would be hidden by the main form.
I have a main form with datagridview containing a list of contacts:
VB
Public Class Form1
Private Db As New DataClasses1DataContext
Private Sub Form1_Load
[Code]....
After saving, I get the correct message ("Saved"), and the DataGridView in the first form gets updated in real time.
But... when I take look at the data (or close and reopen the forms) the data in the database (SQL server) have not changed! What happens!
How do i load the Main form of a WPF so that a seperate thread goes and gets data from the database while the form is in an apartmentstate? (drag-able / movable) I Know this is possible with opening a new window from your main form like this :
Private Sub openOrderWindow()
Dim OrderWindow As Orders = New Orders
OrderWindow.ShowDialog()
End Sub
[code]....
I've tried putting MyBase.ShowDialog() and .Show() and .9000+ other things The only benefit I've got out of using a seperate thread to load from the databse is i can see the screen right away (as oppose to it being a transparent box until it loads) but i cannot move it around or minimize it?is there any way to make it Movable while it loads?
[Code] I want like to check if a file exist on main form, if not: force open settings form. And then when the user is closing the form with exit button = check if the file exist again. If it doesn't exist, close application. It's a huge application and I need optimized on most parts. Also, the settings form is asking the closing question two times.
View 1 RepliesHow can I make the main form grey out/translucent black when a new form opens on top?
View 8 Repliesi am having some trouble in my Windows form application. i have 2 forms1st Main / Parent Form2nd Sub / Child Form (Menu)
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