I'm trying to get a handle on creating my own Interfaces for a project I'm working on. I know the MSDN help shows that all member signatures will become Public when implmented, etc, etc. However, if I implement the IDisposable interface provided by the framework, comments and private members and fields show up! Not only that, but some of the methods have comments and code within!
How did they do that? And can comments, private fields and members, and predetermined code be declared as part of an interface by the average developer?
if for example i have two private sub I declared a local variable on private sub a... is there a way that private sub b could use the variable created on private sub a? Im asking because im in a problem in my app were using global variable is not an option to make the long story short
I have these list of RS-232 strings declared in my public class Public Class TouchInterface Dim WatchTVbtnCmd As String = "rs232command1" Dim VolUpbtnCmd As String = "rs232command2" Dim VolDownbtnCmd As String = "rs232command3" Dim SystemOffbtnCmd As String = "rs232command4" Dim RadiobtnCmd As String = "rs232command5" Dim MusicbtnCmd As String = "rs232command6"
I then have this private sub. For the sake of this thread, what I would like to do is get the name of the label that was clicked which in the code below is already done, convert it to string (not sure if this needs to be done), this is also done in the code below. Next I want to compare the labelnamestring to all the variables in the public class to find out which one it is equal to and then disply that variable which should be my rs232 string in the message box. I have also added "Cmd" to the variable names above so I also need to work out how to add the text "Cmd" to the string to properly compare.
Private Sub Musicbtn_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles WatchTvbtn.Click, VolUpbtn.Click, VolDownbtn.Click, SystemOffbtn.Click, Radiobtn.Click, Musicbtn.Click, GardenVolUpbtn.Click, GardenVolDownbtn.Click, GardenRadiobtn.Click, GardenOffbtn.Click, GardenMusicbtn.Click, GardenMediaCenterbtn.Click Dim labelname As Label = DirectCast(sender, Label) [Code] .....
I am a little new to .NET Developing, and have learned a great deal recently, but I'm stuck with something. I come from an ASP Background, I'm trying to subtract 2 variables, but they don't seem to 'see' one another.
I am wondering if you have a class and in the class you have a function which executes a sqlcommand. Which would u use ? the local variable declaration or the private member command variable.Assuming that the class has a private field called m_Cmd as OracleCommand..i am using oracle db so i use oraclecommand , if sql server then it should be sqlCommand.[code]
I'm trying to make an application that calls a function to create a timer, but I cant use WithEvents or Private inside of a function or sub, Is there any way to do this?
I thought I had this figured out because it presented no errors, but when i tried to run it, I got this exception error:
Object reference not set to an instance of an object.
I am trying to set two private variables:
Private mdatStart As DateTime Private mdatEnd As DateTime
I need to set these dates from a datetimepicker (dtpPickup, dtpReturn), but I don't now how to set it. I have tried using:
Private mdatStart As DateTime = New Date(dtpPickup.Value.Year, dtpPickup.Value.Month, dtpPickup.Value.Day) 'Private mdatEnd As DateTime = New DateTime(dtpReturn.Value.Year,
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?
comparing C# code and VB.NET and the results between the seemingly identical code were entirely different.(Why C# is always winning over VB.NET?)The explanation given is that C# will initialize the class fields, then call the base constructor, but VB.NET does the exact opposite. Is there a technical reason for the languages to be different? At first glance, it seems that either approach is equally valid, but I can't fathom why they wouldn't have selected the SAME approach.
EDIT: As 'Jeffrey L Whitledge' has pointed out, VB6 did not have inheritance, so I don't think we can say 'to keep VB.NET and VB6 more closely related'.
I 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.
I would like to create an interface that brings with it it's own private variables and regions.for example, if you create a class and implement IDisposable, you get all of the following:[code]
give me a good resource that explains the difference between a Private, Public, Shared Functions/Sub/Variables? I normally use Public for Subs/Functions inside of Modules I call from other parts of the program. But I'd like to get more of an understanding of how and when to use them. I want as little as impact to a system that is running my programs as possible, so i guess the key here is I'm trying to just get more proficient in my coding.
I came across a number of new Private Shared variables (of type Hashtables(Of String), initialized in the declaration) added to a partial class for a very large (DataContext-derived) class. This seems sensible to me in one sense because they never change, and making these shared variables ensures that they won't get re-initialized every time a function is called. However, these variables are only used within the scope of one function in the class, and I fear the private namespace of this DataContext-derived class is getting rather polluted, and having these sorts of things exposed at such a high level might be confusing to others reading the code in the future.
Would there be negative performance impact to making these local variables within the function where they are used, or is there some better way to handle this? Basically we are using these 3 hashtables to determine whether anything within particular subsets of properties changed (using GetModifiedMembers and then using the Overlaps function of the hashset to see if any of the modified members correspond to members we care about).
Edit: I caved and took the time to write my own test program, which confirmed that there is a cost to using local variables (which I assume applies generally to all cases -- I doubt there's any case where a shared variable would be slower unless using the shared variable requires some additional logic to do so properly): [Code]
So in this particular case, using the local variable costs about 200%. But in most cases (including my own), the time is probably negligible compared to the overall task. So I guess the question now becomes, how do people generally feel about improving code maintainability at the cost of negligible but known performance impacts?
I just started playing around with interfaces recently and I have a couple things I want to ask. First off I always understood that an Interface cannot contain code, you are merely creating almost a "template" of methods, property's etc...Lets say I have this:
Public Class MyTest Implements IMyTest Public Sub iDispose() Implements IMyTest.iDispose
Last year (2010) I came across a FANTASTIC command that allowed me to take a string of variables with a common delimiter and break it all back out into separate variables (possibly an array) with one statement.
[Code]...
As long as the delimiter was a unique specifiable character, this one-statement command could break it out into elements. my memory and point me in the right direction.
I have a private sub that I have to call in different times with different textboxes when I click a button. So I made something like this private sub [just some things to change D link into V link not really important]:
Private Sub DtoV(ByVal input As String) Dim vlinks As String If input <> "" Then
I am trying to call this private function, but am missing somthing, anybody point me in the right direction Private Function DL_WebPage(ByVal _URL As String) As String This is what I have tried, but with no success: call DL_webpage But this comes up with an error
Probably an easy question to answer...I have 9 buttons on my form
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click etc. and all do the same thing so how can I merge them into the same sub so i don't have to copy and paste a bunch?
VB.NET Dim iString As String If My.Settings.IPBank.Count = 30 Then MsgBox("You alredy have the maximum amount of IP Addresses stored, delete one to add another.", MsgBoxStyle.Information, "Program Error")
[Code]...
I want it to check all of the items in the my.settings.ipbank which is a stringcollection. Before it adds and if it already exists in my.settings.ipbank then i want it not to add it. But it just adds when i run it. And then once its added it says: "Collection was modified; enumeration operation may not execute." But also before i run it. There is a warning saying: Function 'AddTo_IPBank' doesn't return a value on all code paths. A null reference exception could occur at run time when the result is used. Is this something to do with it? I think i have the Next in the wrong place .
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Clicki want help for the code of a button than will enable or disablePrivate Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
i want help for the code of a button than will enable or disable Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
When I develop a Windows Forms app in Visual Studio using C#, every control that I add to my form is by default marked as private, which is what I want.
When using VB.NET, every control is by default marked as Friend (the equivalent of internal in C#), which is not what I want.
Can I just change this default? It seems like surely it's a setting somewhere.
I have code, shown below, that works all except for 1 thing: The variables being passed byRef get passed, but once modified in the else section of the "if me.invokerequired" code of RecordData, the variables are never updated in the calling function. To reiterate, the calling function does not receive the updated data that is in the variables custid and amt.When debugging, I see the data change in the else section of "if me.invokerequired", but once it returns from the callback the data is missing.[code]
I have the following problem with MEF: Interface definition to be used by host:
Public Interface IExecuteDoSomething Inherits IAddinSettings Event DataReceived As EventHandler(Of DataReceivedEventArgs) Function DoSomething() As Boolean End Interface
[Code]...
Everything seems to work fine until the Button2_Click routine is executed, then an InvalidCastException is thrown with the info:Unable to cast object of type 'System.Collections.Generic.List1[SharedLibrary.IExecuteDoSomething]' to type 'System.Collections.Generic.List1[SharedLibrary.IAddinSettings]'.
How can i solve this problem, because the imported object implements both of the interfaces?
