Suppose I have the following code:
Public Class MyDbTransaction
Implements IDbTransaction
Private itsTransaction As IDbTransaction
Public Sub New(ByVal trans As IDbTransaction)
If trans Is Nothing Then Throw New ArgumentNullException("trans")
[Code]...
I have converting this method from vb.net to c#:
Public Shared Widening Operator CType(ByVal items As MyOption()) As MyOptionCollection
Return New MyOptionCollection(items)
End Operator
My complaint is that I do not know what this function can complete. I also want to think of how it is working. I find that "Widening Operator" means that when you cast the cast will work but I don't think I have the full meaning.
How can I convert this to c#?
I have this class: Public Class Foo
[Code]...
In the f = "Bar" assignment I loose the previous X and Y values previously assigned. There's a way to overload the operator to assign to the "Value" member instead of creating a new Foo class? Or a way to obtain the target of the assignment to copy the values??
I have a class that overrides Ctype operator to have conversion from and to String :
Public Class TotoToString
Property value As String
Public Sub New(ByVal V As String)
Me.value = V
End Sub
[Code] .....
Consider I have a shared function:Public Shared Function CalculateAreaFromRadius(ByVal radius As Double) As Double
[Code]...
If I have two or more threads in the same vb .net app and each of them calls the shared function at the same time with different RADIUS, will they each get their own AREA? I want to know for each call to the function if it is using same local variables or each call creates new instances of local variables?Will the answers to above questions be same If I have multiple (2+) single threaded apps and they all call the function at the same time with different RADIUS value?
I had a problem (which is now fixed) but I've no idea why.I have an Ajax AutoCompleteExtender with a WebService method to populate like <WebMethod()> _
Public Shared Function populateACE(prefixText As String) As List(Of String) However this didn't work - I put a breakpoint in, and it didn't even get hit. However... <WebMethod()> _ Public Function populateACE(prefixText As String) As List(Of String) does work (the only difference being not Shared).
Fair enough, but why? If you have an instance of a class then you can access Shared methods of it; if you don't have an instance of a class then you can access Shared methods of it. So what is going on behind the scenes?
i was wondering if it possible to have a condition where lets say you have a column in the datatable called amount and a textbox acting as the filter called say maxamount to set it so the rowfilter when filtering the table will sum the number in the amount column until the number in maxamount is met, then stop and only return the rows where the total sum of the amount column is equal or less than the maxamount value, so i guess if the next row takes us over the maxamount it discards this row and returns the rows previous to it. is this possible using datagridview rowfilter or should i be loooking elsewhere to achieve this?
View 4 RepliesI have an sql table called Stock with two fields called StockID and StockCode. I want the user to select the stockcode from a combo which in turn populates the stockid for that item into a lable on my form. I have already populated the stockcode into the combo but dont know how to compelte the rest.
Imports System.Data.SqlClient
Public Class cbo2
Private Sub cbo2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[CODE]...
I have a form called FrmPracDetails which is built up with a List view called LvwColProc. Therefore when you click a field on the LvwColProc it takes you to another form called FrmColProcessing, here you can make changes to certain fields which are also present on FrmPracDetails. What I want to do is when you make changes on FrmColProcesing and Click the Save Button (which calls the Save function)the changes appear instantly on FrmPracDetails. Please note, FrmColProcessing will always be open next to FrmPracDetails. I have tried to put this code in the Save function present in FrmCol Processing as shown below, but it doesnt Refresh FrmPracDetails form. [code]
View 1 RepliesIs there any way to tell vb.net (2010) to allow expressions of type Double to be passed to parameters expecting Float, without having to use an explicit CSng() calls, other than by turning off all complaints related to narrowing conversions? Given that a Double->Single conversion will never throw an exception, and given that precision loss does not seem to be a criterion for regarding a conversion as "Narrowing" (Long->Double is considered "Widening" despite the fact that it involves an inexact conversion from an "exact-value" type to an "approximate-value" type; a Double->Single conversion merely goes from an "approximate-value" type to a "somewhat-more-approximate-value" type, so it is in some sense less lossy).I know turning off Option Strict would eliminate squawks about Double->Single conversion, but that is incredibly massively overkill. Is there any way to stifle all complaints about Double->Single, without stifling other possibly-useful squawks?
Edit:If Microsoft isn't going to allow code to be written in the most logical fashion, would it be preferable to litter the code with CSng() every time I call graphics methods, or define NewRectF and NewPointF methods which accept doubles and then use the RectF/PointF overloads for the graphics methods?
I have the following line of code in my program:
JCL_History.Enqueue(JCL_History(I))
This JCL_History object is basically a Generic.List encapsulated in a wrapper and has the following method:
Public Sub Enqueue(ByRef value As String)
If Members.Contains(value) Then
Me.RemoveAt(Members.IndexOf(value))
[Code].....
In my testing I have 2 items in this JCL_History list. When I call that first line of code I posted (the one that invokes Enqueue) with I = 1 I expect the first item to be shuffled to the bottom and the second item to be shuffled to the top.
After the thread returns from Enqueue I notice that this is exactly what happens to my list, HOWEVER if I hit the "step_in" button after the execution of Enqueue I go into the Default Property's set method where Index = 1 and value = and it screws everything up, because the item that got shuffled to the end (index 1) gets overwritten by the item value shuffled to the top.
So basically the set method on the default property is getting called at what I think to be a completely ridiculous time. What gives? By the way I'm running VS2005 on XP.
I have a class like this:
[Code]...
It works, when I make getBar methods public, but I don't want to expose these unneccessarily. Why I can't call private shared methods from a public one in the same class is over my head. I'm using .net framework 4.0 in a web application.
I am tightening up my coding with the Option Strict set to ON. It has now produced alot of errors. An example of this is:
If AllocatedDGV.Rows(i).Cells("RoomNumber").Value = RoomsAvailableDGV.Rows(j).Cells("RoomName").Value Then
It gives me the following error: Option Strict On disallows operands of type Object for operator '='. Use the 'Is' operator to test for object identity.
I need to write an interface to get data to/from our data files.
We have a low level class that holds field values for each record read from the files.
This just holds two values, the value read from the file (DBValue) and the updated value that may need to be written back to the file (CurrentValue).
These values may be any of the standard value types (integer, date etc) or a string.
Either value (DBValue or CurrentValue) may be null if not defined.
I have written the class to manage this data which works fine while option strict is NOT on.
But we have an office policy of having option strict on all the time.
When I put option strict on, my object value comparisons fail with the error: "Option Strict On disallows operands of type Object for operator '='. Use the 'Is' operator to test for object identity."
Question, how should I change the following code to handle option strict on ...
This is all running on Visual Studio 2010
[Code]...
Possible Duplicate: Is there a conditional ternary operator in VB.NET?
Can we use Coalesce operator(??) and conditional ternary operator(:) in VB.NET as in C#?
I've taken over the maintenance of the website (ASP.NET VB) and on one particular page I noticed the below code
Inherits System.Web.UI.Page
Public Shared UserNumber As String
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
[Code]....
My question is whether the variable UserNumber can be accessed or changed by any other user than the current one?
Given in the following language specification, for me at least, calling Db.Foobar() [In the following code] does not indeed call off to the Shared Constructors of the base classes. I am curious as to a) is this my own fault for doing something wrong or b) is this an error in the language specification[code]...
View 2 RepliesCan you look at my coding and let me know what I'm missing or doing wrong?I have a SSRS report that is called from a ReportViewer control and the ProcessingMode for this control is Remote. The report also has 1 parameter in it's DataSet.In the code I placed a MsgBox to make sure the code is finding the parameter and returning the parameter name. I am trying to stick the value of 10 into the parameter for playerID 10. Data for this player does exist.
I believe I need to add some more code to make this work but I'm not sure what else to add.
When the code executes the report is displayed but no data is shown in the report.
[Code]...
I recently found an awesome tool called "Freemind" that is called a 'mind mapping' program. It's similar to MS Visio but way cooler and more automated.I reeeallly would like to integrate this into a VB.net Form, but how?
Has anyone seen or heard of mind mapping inside VB.net before? Are there programs out there already that work with VB.net or anyone have an example they have seen / built that works?
have a look at this code Dim colors() As KnownColor = CType(System.Enum.GetValues(GetType(KnownColor)), KnownColor()) Since CType is a function that returns DataType ,But here as in the code it seems that CType() is returning array having values that is assigned to color() array. How this is happening?
View 3 RepliesI have a number of different object types that I would like to pass into a function. All my objects are created from classes with a .Description property. Is it possible to determine the type of object for use as the 2nd parameter in a CType call at runtime? e.g. Debug.Print CType(MyObject, TypeOf(MyObject)).Description (I have Option Strict On) I get errors when I do this.
View 4 RepliesIn vb.net, I got an Enum defined As Integer:
Enum enUtilityTypeDetailStudentEntryWorkflow As Integer
enUTDSEW_Default = 379
[code].....
This works but it adds a lot of noise to the code and it seems like the Enum is already defined as an Integer, making me think, why do I have to assign it again?
I want to perform equality comparison in VB.NET and cannot get it to work. Error: value of type Boolean can not be converted to System.Drawing.PointF
[code]...
I cant understand why this does not work! Hope for your intelligent answers ;)
With
CType(Controls(PicsGame(GameCount)),
PictureBox)
BorderStyle =
BorderStyle.None
Is it possible to change a datarowview object to an integer?
View 3 Repliesdim testpanel as new panel
dim test as CType(testpanel, Control))
msgbox(typename(test)) ' it gives me "panel"
'i dun get it, how can typename of test give me Panel when i explicitly call it to be converted to a Control type?
I am an experienced C/C++/C# programmer who has just gotten into VB.NET. I generally use CType (and CInt, CBool, CStr) for casts because it is less characters and was the first way of casting which I was exposed to, but I am aware of DirectCast and TryCast as well. Simply, are there any differences (effect of cast, performance, etc.) between DirectCast and CType? I understand the idea of TryCast.
View 2 RepliesI turned option strict on, wich gave me some errors. The errors are quite easy to fix, but it seems like there are several ways of doing things. [code] 'previoustime' is declared as a TimeSpan, and the column "sluttid" is defined as a TimeSpan-column.Now, as far as I know, there are two ways of solving this; using CType and using DirectCast, like this: [code]
View 4 RepliesAssume that I have this declaration (according to MSDN):
Private Declare Function PostMessage Lib "user32" ( _
ByVal hWnd As IntPtr, _
ByVal wMsg As UInteger, _
[code]....
And this is how I use it:
PostMessage(hWnd, 516, CType(2, UIntPtr), CType(0, UIntPtr))
Option Strict is turned On. So the questions are:
1. Do I need to use UIntPtr in declaration or it will be better to use UInteger?
2. Do I need to use CType function in these cases or there is a better way for this or I need to avoid declaring pointers?
does your IDE ever get amnesia?in the line before it is clearly defined.in the following line it is not.Maybe it's a faulty translation from Tangible Software.the C example i'm looking at:
IAnimatedMeshSceneNode* newNode = (IAnimatedMeshSceneNode*) oldNode->clone();
translated as:
Dim newNode As IAnimatedMeshSceneNode = CType(oldNode.clone(), IAnimatedMeshSceneNode)
had to make a dummy for it because i can't use arrays with CType.
