.NET Support Automatic Getters And Setters On Properties?
Apr 7, 2011
In C# I can do this: public string myProperty { get; private set; }This is referred to as an "automatic getter/setter" (from what I've heard). Does VB.NET support these? So far, with my properties, all I can do is this:
This is probably a stupid question, but when accessing an attribute from within a class is it generally better to access the private variable directly, or access it using the getter/setter? Of course the whole point of encapsulating attributes is to allow changes to the underlying code without affecting anything that uses it. Should that also apply to the class itself? Or is it a case where the class should have full knowledge, and so shouldn't have to use the getters/setters?
In VB.NET, what are the advantages of using the Property keyword rather than:[code]Coming from Java I tend to use this style rather than Property...End Property - is there any reason not to?
Looking at the new VB 2010 features, I stumbled upon support for Auto-Implemented Properties.Since I'm working with C#, this seemed quite familiar, but I noticed that VB did add a feature I would love to have in C#: setting a arbitrary default value for the auto-implemented property:I really like the clean usage of auto-properties in C#. This would save us the effort of introducing a backing field and hooking it up to the property everytime we simply need a default value, thereby cluttering up the code unnecessarily.I was wondering why this wasn't introduced in C# as well? What could be the rationale for not doing this? Is a syntax discussion going on, or are there technical limitations to implementing this?
I have observed a behaviour in VB.net where property setters get called more often than seems necessary, in conjunction with calls to the sister setter method.
Public Class Form1 Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Console.WriteLine("Calling WorkReferenceTypeByReference") WorkReferenceTypeByReference(ReferenceTypeData) Console.WriteLine("Called WorkReferenceTypeByReference") [Code] .....
Note the spurious call to the property setter following the method execution. I am supposing this behaviour is produced as a safety measure against inadvertently modifying the underlying property, despite this potentially being the intent. This behaviour in the case of ByRef vs ByVal usage is easily solved by choosing appropriate ByVal keyword, however hase recently noticed a more insidious behaviour, one that has caused a stack overflow of repeated calls, since the setter call would update a value that called the getter only.
Public Sub DoSomething() Dim a As New CustomObject(anotherObject.AProperty(getterArgument)) End Sub Public Class AnotherObject Public Property AProperty as SomeType [Code] .....
In the previous example, calling DoSomething() would fire the AProperty getter method, but then after that usage, would fire the setter method, which by program logic calls DoSomething() again. It is the automatic calling of the setter that puzzles me.
I compiled some VB6 code on my Win7 x64 machine and the result .exe will not run correctly on any other machine. VB6 code is just a new template .exe file with one button, a reference to "Microsoft ActiveX Data Objects 2.6 Library" and the following code in the button press event: Dim db Set db = New ADODB.Connection It runs correctly on my machine, but no others (even other Win7 x64 machines) (Update: I found TWO other users where it runs and one of them is Jeff Atwood!, but most machines have the same problem)
I'm making a control and I am trying to finalize my design time properties grid. I have several List(of Class) items as public properties and when I click on the design time menu (while testing the control) there is the word "Collection" and a button with an ellipsis (...) that brings up a neat pop up with the buttons Add/remove and all of the public properties of the collection's class on the right hand side. Basically for a non-collection instance of a class (with public properties) I'd like a similar button to show up. I know I could put all of the properties in the main control class and group them, but I like the pop up box feature. Anyway to duplicate this? (think font grid item etc.)
In the form design I set up a TableLayoutPanel, 20x20 cells and in cell (1,1) a PictureBox (called Target) containing the image of a small target. The properties box for Target shows some very promising properties, Column and Row - and if you overwrite the values in the properties box, the PictureBox obligingly shifts to the corresponding cell position in th design. However in VB it is not possible to refer to Me.Target.Row or .Column - neither appears during coding in the menu of properties, and deliberately coding either of them produces an error like
Error 1 'row' is not a member of 'System.Windows.Forms.PictureBox'.
1. Why does the properties box show properties that cannot be altered programmatically?
2. How can my program move Target around in the TableLayoutPanel?
I'm working on a Hazardous Materials label printing program. One of the options is to do an "NFPA" label. Since there are 4 values required with 4 or 6 options, the ratings are entered via radio buttons in a group box. That's working okay. I display values in the NFPA diamond as they're entered: left quadrant blue, top quadrant red, left yellow, bottom red. I'm having trouble with the label in which the rating will be displayed on top of a jpg diamond for the white. In this quadrant the text can be up to 4 characters. I can accept the text going into an adjacent block a little, but the corners of the label overlap into another quadrant/color. I reduced the font size which solved the overlap problem but the font is then too small and looks terrible. I tried to make the background of the label transparent to let the color come through correctly but that's not a valid value for label.background. I'm figuring that the transparent background is the best solution. What can I use that will accept a transparent background so the color shows through?
I'm trying to set the transparent property via label properties properties, not via code. Here's the code if it makes any difference:
Public Class NFPA Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Close() End Sub
How to change all properties of a form to properties of other but don't change important properties like Owner,Handle, OwnedForms, Parent,HasChildren,Controls and ... .I have a child form that i want it to provide controls of Form.The background form provides Aero frame and child form is a transparent form in it.I want it because I want to draw buttons with system style in Aero in Windows Forms.This is my own code but it does not work good (ForeForm is child form):
For Each Propertry In ForeForm.GetType.GetProperties() Select Case Propertry.Name Case "AeroBackgroundEnabled", "FormBorderStyle", "TransparencyKey", "Parent", "Owner", "ShowInTaskbar", "Handle", "HasChildren", "OwnedFo[code].....
Additionaly:I wrote a great Aero Form.I don't publish current version (1.2) that supports Aero Blur,RealTime Aero Color change,extend Basic theme?
I have my own class of graphic objects, and now I'd like to allow a user to right-click on one of those within the application and see a properties window. Is there a pre-built dialog or control for displaying properties at runtime? I'd like to have something just like the IDE properties window button for my application.
Public Class LOA Private Sub PrintDocument1_PrintPage(ByVal sender As System.Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage
i completed sending mail automatically. but i have an issue bothering me.i am using gmail as my smtp server and database as access.i am able to send mails but when i give a wrong address it is redirecting to my mail stating failure of delivery but i want that to be displyed on the console once i send the mail and also if net connection is not available i want it to show network connection is not available. here is the code so far
Dim ds As New DataSet Private Sub FDaily_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
I am designing an Windows application in Vb.net. When ever I run the application it needs to check the current time and remind me some tasks which I have defined. In what way can I do this.
I want to send an automatic E-mail based on the date. If the current date is greater than 5 days than the current date field in the table then i need to send an E-mail to the designated person. I am using VS.NET2003/VB.NET/ASP.NET/SQL Sever 2000.
I'm looking for visual basic.net code (for visual basic express) to take automatic screenshots (timeout=60 seconds) for application testing. But every code has a lot of bugs:For example: [URL]Errors like:
Error 1 'Protected Overrides Sub Dispose(disposing As Boolean)' has multiple definitions with identical signatures. Error 2 'Private Sub InitializeComponent()' has multiple definitions with identical signatures. Error 3 'components' is already declared as 'Private components As System.ComponentModel.IContainer' in this class.
in vb.net while entering a new entry i want to assign a record a unique id like in case of numeric i do this way
Dim ItemID As Integer KAYAReqConn.Open() SQLCmd = New SqlCommand("SELECT ISNULL(MAX(ItemID),0) AS ItemID from MstItem", ReqConn)
[Code]....
in this case m using itemid as a unique id and the format is 1,2,3... and m finding out the max and assigning to a new record but how to assign if the previous id is of the a00001,a00002,a00003,a00004...so on. how i do i produce a unique id in this case
I'm very unfamiliar with this, I've heard about running sql automated jobs, but how Can I run an aspx page daily?? Basically When the page loads up, it constructs an email and sends it out..
I have the following situation: An interface (Windows forms) to a dataset. It has binding navigator, binding source, table adater etc operating with a dataset. How can I make a textbox for an ID field automatically generate an appropriate number for the ID? Just like the sql server direct database editor generates an id for fields with the "is identity" and "auto increment" properties on.
I have a problem regarding an access file I attached to this post.I have a table which contains the costs(VVGK) for each month in 2008, 2009 and 2010. For each month we have planned costs(Plan) and the real costs (Ist). And what I want to realize is that in the report in the top right it automatically displays the percentage difference between the plan and real costs of the last month. And this should then be automatic every time I give new input(new month, new VVGK Ist).