OK, I'm working on a project and i need to access the property of a usercontrol which I have set.Here is the code in the UserControl
Private Color As Color = ColorTranslator.FromHtml("#000000")
Public Property InkColor() As Color
Get
[code].....
Does the memory used in declaring variables are reclaimed by the OS when these variables go out of scope?Does the memory used be released by setting thier value to nothing? if not, then how can I force the garbage collector to run or excecute at a certain/desired time..How about in Windows Forms..How can we make sure that the memory used in initializing and showing forms be released if those forms were closed?
View 13 RepliesI actually came from VB6 and starting to learn VB.NET. I saw this line of code which I cannot understand how it works nor how it goes.
Private MAX_VALUE As Integer = (1 << 14)
I have just been experimenting with nesting classes within a User class I had already created.
E.g.
Friend Class User
[Number of Properties...]
Friend Class Address
[code]....
I get the same error message!!! "Declaration expected". Also I notice the variable's name is not coming up in intellisense. I have not come across this before as declaring an using variables and objects has been straight forward up until now.
The user clicks a button, a new form is generated where the user enters his/her password? How can I keep an in-memory copy of the username?
For instance in web forms, I can just use Session ("User"). How can I replicate this with winforms?
I've created a 30 point wizard. Every step gathers between 1 and 3 variables. I've created a module and publicly declared the variables there. At the end of the wizard, one master form opens, gets all the variables, and displays them on one form. At this point calculations are run too which populates more variables. This works fine for one instance of the process.
the user may want to be running two instances of the wizard at once. Obviously, if the previous wizard is part complete and they start a new one, the variables are going to get crossed or replaced by the new wizard.Is there a way for the variables to be declared publicly but used in multiple instances?
What's the proper way to declare variables in a class? I've been doing something like:
'in a class
public shared teststring As String = "first"
'on a code behind
[Code]....
with shared variables loading a second window or reloading the page (without clicking the button) renders the hello world string. so how do I declare variables in a class but make it per instance?
When I am writing a sub or function that does some calculations etc. I often need a loop or a integer variable to count.
An example:
''' <summary>
''' Compare elements with the new data and perform all necessary actions.
''' </summary>
[Code]....
As you can see, variables like timespan, nullCount and seconds are declared within this sub.
My question is, is it better to declare these in the class? I can imagine that would boost performance.
Sub Application_Start(ByVal sender As Object, ByVal e As EventArgs)
Dim chatters As List(Of Chatter) = New List(Of Chatter) chatters.Add(New Chatter(New Guid("CD863C27-2CEE-45fd-A2E0-A69E62B816B9"), "Me")) chatters.Add(New Chatter(Guid.NewGuid, "Juan")) chatters.Add(New Chatter(Guid.NewGuid, "Joe")) Application.Add("Chatters", chatters)
[code]....
I am unable to understand last 3 lines that are bold and underlined. Please what is hppening here. Chatter and Chat are two classes defined in App_Code folder. Is there any sight that contains all possible ways to declare and initilaze variables and data structure:
Dim chatters As List(Of Chatter) = New List(Of Chatter)
I need to write a simpe calc. program to add, mutiply, subtract and divide. I want to have two textboxes that I enter numbers in and when I click a button, +,-,/ or * a third text box will display the result.Rather than declaring my variables inside each instance of a click event I would like to declare them globally so I just need to perfom the calculation on them and display result. However declaring them globally doesn't work for me. I;ve tried the variables inside the btnAdd click event which works, but as I said I'd prefer to declare them onece globally.
Public Class Form1
Dim number1 As Double = CDbl(txtNum1.Text)
Dim number2 As Double = CDbl(txtNum2.Text)[code]...
recently started converting our project from 1.1 to 2.0
It was fine with the following:
Public ghtAllAppMsgs As New Hashtable(300)
Now it is complaining to change to the following is this the right way:
Public ghtAllAppMsgs As New System.Collections.Hashtable(300)
This is under global.vb class file: here are the imports i already had in this file:
Imports Microsoft.Web.UI.WebControls
Imports Microsoft.Web.UI.WebControls.MultiPage
Imports System.Web
[Code]......
I am writing a program and i need to declare matrices but there will be a different number to declare everytime the program is run so I was wondering if anyone knew how to declare them inside a for loop
eg.
For i = 1 to NumberOfMatrices
Dim matrix i (5,5) As Double
Next
I am new to the forum and new to the visual studio set up and have been working at a practical at home and have ran into some difficulty. The notes say that I am to declare several module variables below the section entitledI have the rest of the form complete but have been unable to locate where I am to place this code
View 1 RepliesI'm new in .NET programming.I have a class Form1 that includes Button1_Click event.Button1_Click creates a multiple Text Boxies at run time)Here is the class:
Public Class Form1
Dim shiftDown As Integer
Dim counter As Integer
[code].....
i have read on the msdn and know properties statement used for declaring the name of a property, and the property procedures used to store and retrieve the value of the property.i learned about structure of it. but i cant figure out it clearly. [code]
View 3 RepliesI am at a loss to figure out why this code results in 2 errors when I try to Parse it inthe SSMS.
@Collection varchar = Books,
@Title varchar = 0,
@Authors varchar = 0,
[Code].....
I think that I re wrote this query ten times todaday and continue to get errors and don't know what my problem is
There are underlines in red under the 0 in the BookLoanStatus and under all of the parameters in the SQL.
I am new to Visual Studio.NET but very familiar with the old ASP (using DreamWeaver).I am unfamiliar with this system of having seperate files for VB code and HTML, in my Visual Studio project I have a Default.aspx file and a Default.aspx.vb file. Now I want to declare a variable that will be accesible to all my functions on the Default.aspx.vb file. I.e. if a user clicks on one button and it launches a Protected Sub called Button1_Click, I want that button to be able to read or write to that variable and then if a user clicks on another button, I want it to likewise be able to read and write to that variable.So where should these variables be dimmed?
At the top of the aspx.vb file? Before or after the line that says "Partial Class _Default"?Or at the top of the aspx file? (Within <% %> brackets?)
I come from C# (use VS 2005, .NET 2) and I know that when I declare a private variable I can "extract" from it the corresponding "property". In VB.NET I've declared a lot of properties (in the diagram class designer). Now am I forced manually adding the corresponding private fields?
View 4 RepliesIs it possible for a class of exposing a type for function returns, without allowing users of that class to create variables of that type? A couple usage scenarios:A Fluent interface on a large class; a statement like "foo=bar.WithX(5).WithY(9).WithZ(19);" would be inefficient if it had to create three new instances of the class, but could be much more efficient if the WithX could create one instance, and the other statements could simply use it.A class may wish to support a statement like "foo[19].x = 9;" even when foo itself isn't an array, and does not hold the data in class instances that can be exposed to the public; one way to do that is to have foo[19] return a struct which holds a reference to 'foo' and the value '19', and has a member property 'x' which could call "foo.SetXValue(19, 9);" Such a struct could have a conversion operator to convert itself to the "apparent" type of foo[19].In both of these scenarios, storing the value returned by a method or property into a variable and then using it more than once would cause strange behavior. It would be desirable if the designer of the class exposing such methods or properties could ensure that callers wouldn't be able to use them more than once. Is there any practical way to accomplish that?In formulating a question, it's difficult sometimes to draw the line between complicated usage cases, and simpler usage cases which aren't quite so important. Here's another usage case, and one closer to the one I'd be most interested in (though I'm also interested in Fluent chaining; being able to have something behave like a C++ reference to a value type would be nice, but probably too much work to bother with).I have a type which is somewhat like the Windows registry, in that it is a hierarchical collection of items, each of which may have a string value, an integer value, and/or a nested collection of items. I wish to be able to support the following types of usage:[code]As for the Fluent interface, my thought would be to have the WithXXX properties return a new instance of a derived class which shadows (not overrides!) the WithXXX properties with versions that simply modify the current instance. The return object from WithXXX would be known to be of the derived class, and would thus use the shadowed WithXXX methods, but once it was assigned to a variable, it would be regarded as an instance of the base class, so the next WithXXX would create a new instance.
C++ a stronger concept of value types than C# or vb.net, including the very useful concept of references to value types; it ensures that references to value types cannot be persisted outside the scope of the type in question. Unsafe code in C# can use pointers to value types, but they don't have the protections offered by C++ references.
I'm wondering about the performance differences between imports and inherits in a .net app.I currently program by creating multiple classes that logically define my objects. e.g. a class for customers, users and product.When i want to use these classes in a page i have to import them eg. "Imports Custmomers" and then later in my code i have to create a variable and datatype it before i can use the sub routines and functions from class.I understand from a coding perspective this keeps it all neat and tidy.So my question Would it be not better to combine all my classes into a base class, inherit that base class, rather than import it, when i want to use it and so cut down on the extra declarations and associated code that come from importing a class; and if i did this would it aid performance?
View 1 RepliesHow do I say, in an if then statement, If this image is currently displayed in a picturebox then a certain value is assigned or a certain event should happen?
View 9 Repliesbasically i was wondering if we could inherit shared variables but restrict its scope to only that of the class itself.
Class A
Public Shared shared_variable as Boolean = true
End Class
[code]....
when i do this A.shared_variable = False, B's shared_variable also becomes false. how do i stop this?i cannot remove the Shared keyword because shared_variable should be able to be accessed without an instance of the class?
Why use simple properties instead of fields in C#?
If I have a class, does it matter if I use a Variable instead of a Property? I mean, unless I need something to run during the get/set time period, does it really matter?
I have several classes that use a bunch of strings for directories, arguments, etc.
At the moment, they're all just declared globally within the class like so:
VB.NET
Private str1 As String = "path"
Private str2 As String = "path2"
Private str3 As String = "arg"
To me, that looks awful and doesn't seem like the proper way of doing things. So, I was thinking, should I make a property for each string and then use a constructor to initialize them?
Would that make a difference at all? Is that the proper way of doing things?Also, some strings are used in a ton of different places and they're basically just being copied from one class and pasted into another. So, do you think I should do what I suggested above, but with a class whose sole purpose is to house those strings so that the code isn't duplicated a million times everywhere? Would that be the most efficient way of doing things?
[Code]...
I am programmer from some time only, I have certain doubts in fundamentals, could you please clarify on the following:Case 1:
[Code]...
Does case 1 and case 2 yield same result, I mean is a private value necessarily in there?, can we use property itself to use its own value in its Set and get statements?
i was wondering if we could assign variables into the values of attribute properties like say:
<System.Xml.Serialization.XmlType(namespace:="Result" + x)>
where x is a string with value "qwe" so basically we get the output:
<System.Xml.Serialization.XmlType(namespace:="Resultqwe")
Ok so my boss told me that I can't use DataSet's and dataadapter and such like this because it isnt good for scalability. So, I must change the way I have my 28,000 records binded to my form. The problem is, I'm only 3 months in with VB.NET and I don't know of any other way to accomplish what I need to do. I was reading somewhere that I can use a Class as my "Order" and I can bind the variables/properties to the form and with this, I can navigate through records while having controls on each important part of the "Order". Unfortunately, I don't know what I'm doing, this is as far as [code]Any guidance as to what I am to do from here in order to pull the data from my database and bind to the property, then to a text box/combo box, and a way that I can use my binding navigator to go through the many records.
View 13 RepliesI have a bunch of private variables I've typed out and I want to put all of my corresponding Public ReadOnly Properties in a bunch below them.Is there some way of copying ten lines of
Private _myVar As String
and pasting in ten sets of
Public Readonly Property MyVar As String
Get
Return _myVar[code]....
I'm currently copying the whole bunch of variable declarations, Find+Replacing Private _ into Public ReadOnly Property then going line-by-line expanding the definitions and writing return statements.how to avoid all this nonsense in the future, as I'm developing on a virtual terminal server, and the input lag on my little copy/paste/type operations on the code is driving me up the wall.
What is the impact of creating variables using:
Dim ds as New DataSet
ds = GetActualData()
where GetActualData() also creates a New DataSet and returns it? Does the original empty DataSet that was 'New'ed just get left in the Heap?
What if this kind of code was in many places? Would that affect the ASP.NET process and cause it to recycle sooner?
I've implemented the localization in my windows application with no problem for the label or command button which have a fixed text.
My problem is related to the label which text is merged with some variables or object properties.
E.g.: vb label1.text = "There are " & myDataGridView.Rows.Count.ToString() & " items"
So, how can I set (if it's possible) the localization for these labels? I've this kind of assignment in modules and not in the form. It's possible to set a resources file also for modules?