I have an application that has several forms in it. On form #1 I am declaring the variables:
Public payPeriodStartDate, payPeriodEndDate As Date On form2 I have this:
Public Class Form2
Public payPeriodStartDate, payPeriodEndDate As Date
Private localVariable As Integer
What I'm trying to do is to call payperiodStartDate and payPeriodEndDate and to use those variables in the following query:
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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]
View 15 RepliesIn a form I am designing I have a picture box. I want this picture box to display an image from My.Resources. However, the picture to be displayed will change based on conditions. I have written a statement to store the name of the picture I want to call in a string variable called strPicName. So how do I properly use the string variable to get the line of code below to work?[code]...
View 3 RepliesBelow is the code i am using to read and update the system environmental variable. This code is working fine when i am executing .exe on Local Machine. I am getting problem when i try to access this .exe from Browser(using citrix i am doing this) and invoke. when i invoke from browser its going to catch block and displaying MsgBox("Unable to Create LDAP Key.
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I am developing an application where I need to make use of multiple values during the run time. These values are configuration setting of the application as specified by user and are stored in a database (more than 50 in number containing strings/boolean and numeric). I have defined a structure to contain all the variables that will store this information. At start of app, I retrieve all values from database and fill the structure which i can use when required. I am wondering if it is a good idea to declare too much of variables and keep them alive during the run-time as compared to retrieving the values from database every time it is required?
View 4 Repliesi have an issue with scrolling a datagridview (VB.Net 2010) using the mouse wheel i created a mousewheel event an i am catching the mouse-wheel movement up or down i created a scroll event and set the boundaries for the scroll, but i have no idea how to combine both procedures:
Mouse wheel event Public Sub grdMouseWheel(ByVal sender As Object, ByVal e As MouseEventArgs)
Dim RowIndex As Integer = grdAccountTypes.CurrentRow.Index
If e.Delta < 0 Then
[code]....
I have a DataGridView that is bound to a DataTable. I was using AutoGenerateColumns=true but I changed it to false so that I could manage the columns myself and then I started getting an InvalidProgramException in the event handler for DataGridView.CurrentCellDirtyStateChanged. When this event handler calls another method called CheckFilter() it throws the exception. It does not enter the method when I step through the code so the exception happens when the method is called. CheckFilter() is a private sub with no parameters. The exception message is "Common Language Runtime detected an invalid program". I am using vb.net with .net 2.0 and Visual Studio 2008 on Windows 7.
View 1 RepliesI am trying to use a bound datagridview and through the add button on the bindingnavigator adding a new row to the bindingsource and then pass two variables to the datagridview in the new row so they can be associated with the proper ids. I then have a save button for when the end user is done inputting the rest of the data for that record.
The code is below:
Private Sub BindingNavigator1AddItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
AddressesBindingSource.AddNew()
AddressesDataGridView.CurrentRow.Cells("caseNumber").Value = Me.CaseNumberTextBox
AddressesDataGridView.CurrentRow.Cells("interestID").Value = Me.InterestIDTextBox
End Sub
I am attempting to convert and Access CMS to VB and possibly vb.net.
the datagridview seems more complicated the I thought it would be my problem is: how can I if I added three columns to my datagridview, let the program insert something with 2 variables and in the last column i would have to do some calculations with the column2 (like the sum of all rows in column2)
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I am using the DataGridView in Visual Basic 2008 Express with an Access 2000 database.
What I'm trying to do is allow the user to click on the Row Header and capture the contents of the 4 cells in the row to 4 dfined variables. I know that I can capture each cell individually by using the CellContentClick event but this would require the user to click 4 times rather then just once.
Im working with a DataGridView with an imported CSV file where the values are delimited with (,).. The grid works perfectly fine. My ultimate goal is to hide the grid out of view from the user and access the data in the grid based on the coordinates of the grid specified i.e (The cell in column 5, row 6 contains the value "Taco") and I want to save that value to a variable...Eventually I want to loop through all the values of a column and save them to individual variables to be later used. So far, this is what I have...
Dim sReader As New StreamReader("book1.csv")
Dim Record() As String
For x As Integer = 0 To 17[code]....
Presently, that will only display the data in column 0, row 0 in those labels...
Note: 17 in the for loop is the amount of columns in the data i provided.. that number will never change.
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.
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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 define some global variables of a class as follows:
Private Class MyClass
Private var1 as Decimal
Private list1 as List(Of string)[code].....
But I found that after this form is closed, all above variables, var1, list1, list2 still exist in memory. I thought they should be collected by gc since the form is already disposed as I confirmed.
Add: I have monitored half an hour after the form is closed. But these variables are not collected by gc. I have an automatic update procedure on the form which uses above variables.Since the above variables still hold values, the automatic update procedure is always called which causes exception. (One quick fix is to check if form.isDisposed in update procedure. But I do not think this is elegeant. Besides, these variables occupy memory.)
I am developing a program where i will download and save an xml file from a url as abc.xml. I open the abc.xml in a datagridview with a dataset without problem.I am confused how can i read raw per raw the datagridview and assign the data in a database table? i am using vb 2008 + msde2005 express.I show the whole content of the xml file in the datagridview with the following [code]I dont know how to create a loop where i can read the datagridview line by line save data in variables (ex.strings) and save it in a databese table?
View 6 RepliesDoes 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 RepliesQuestion 1: What is the difference between "Background Worker" and "Worker Pool" as indicated within the MSDN samples provided.
Question 2: I noticed while using, AddressOf _Function_, variables cannot be passed; what would be an efficient solution to this?
Question 3: While using multithreading is it required to invoke before setting variables, or only form properties?
Question 4: While using System.Net.Sockets is it safe/efficient to use Application.DoEvents while waiting for new data; or would be using a Do While loop be fine without DoEvents since the action would be multithreaded? Note: there can be up to 2000-3000 sockets in use at a time.
I'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 a C++ application exe that uses a C++ dll. I don't have the source of this C++ application and cannot rebuild it. But I know that it uses the traditional LoadLibrary and GetProcAddress to access individual functions in the dll.For some reasons, I want to replace the C++ dll with a VB.NET dll. The dll is not and ActiveX and is therefore not registered.I think I cannot use a class but a module since the C++ exe application does not expect any class in the dll. In all my attempts, I could not have the inner functions of the VB.NET to be called by the C++ exe.How should I write the VB.NET dll?
View 2 RepliesI do realize that a number of questions regarding calling a DLL from vb.net have been raised. I have implemented the DLL from vb.net. I would like to know if the calling procedure is correct or should I be calling the DLL in a different way?
C++ DLL prototype
extern "C" int FitCurve(int solid_or_fluid, int prop_id, int fit_id, int N_points, int N_terms, char *file, double *x_data, double *y_data)
I'm not sure whether this is a VB forum question or a C++ question, but I'll try here first. I have an API library written in C++ (including source) which compiles to several DLLs. I want to call the functions in the library from VB but I can't get the parameter passing right.
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The above example runs but returns nothing. If I change DeviceName to ByRef, I get protected memory errors.
The full library and documentation is available on the internet if anyone would like to download it and I've successfully compiled it with VS2010.
I have a dll which has one function and I want to call this function from Visual Basic 2008. I tried every solution, but I couln't get it to work,
The original declaration is the following in C++
extern "C" CSSM_API void GetOptimalCSSMShaderParams(
float* outProjMatrixArray
,float* outCtrlMatrixArray
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I want to connect to SAP and call RFC from VB.Net 2008.I have done it with VB 6.0 But not getting success in VB.Net I used following code in VB 6.0
Set ctlLogon = CreateObject("SAP.LogonControl.1")
Set oConnection = ctlLogon.NewConnection
oConnection.User = "SIILRFC"
[code].....
I have followed instructions on Best way to use a VB.NET class library from a C++ DLL? but being new to VB I don't know if I've got the VB part right let alone the C++. here I'll correct the code below for posterity's sake!
Here they are: VB first; the project is a Class Library, all settings default except that "Register for COM interop" is switched on in the project properties.
Public Class Class1
Public Sub New()
'do stuff
[Code]....
is the VB correct? Do I need to add anything like an interface to it? Assuming I want to call it over COM not C++/CLI, how do I do that. (This seems like the logical choice as the client already calls other stuff over COM; however, I'm not sure where to get the IDispatch pointer from, in my other code it's passed to me by the client). If I went the C++/CLI route, when moving up from toy project to actual implementation, that would mean changing my existing C++ code from "no clr support" to "/clr" - is that likely to break it?
I have a C++ application exe that uses a C++ dll. For some rasons, I want to replace the C++ dll with a VB.NET dll. The dll is not and ActiveX and is therefore not registered.I cannot use a class but a module since the C++ application does not expect any class in the dll. In all my attempts, I could not have the inner functions of the VB.NET to be called by the C++ exe.How should I write the VB.NET dll?
View 4 RepliesThis might seem like an insanely easy question, but I cant seem to find an answer anywhere to it. I'd like to think that I am decent at VB but while I was learning javascript the other day I found something that seemed awesome and now I cant figure out how to do it in VB.in javascript it looks like this
var someValue = getThatValue()Its both calling and setting the value from the getThatValue() sub. what is the VB equivalent?
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In C# I can do this:new SomeObjectType("abc", 10);
In other words, I can call new without assigning the created instance to any variable. However, in VB.Net it seems I cannot do the same thing.New SomeObjectType("abc", 10) ' syntax error
Is there a way to do this in VB.Net?
I was using .NET for development an SAP application but recently, it always shows me the message below:
failed to call remote function module
I didn't change any setting or source code. But it still has the problem.
i have been deploy webservice in vb.net .
is there will be any problem if i will cal the webservice from c++ (version 6) or Microsoft Access VBA?
By security reason I ask this... Can .cs or .vb files to run in any way without calling those in asp.net?
View 2 RepliesI have a need to create a Tcl extension that calls a managed .NET DLL/Class Library. Currently, the structure of my application is Tcl > DLL Wrapper (C++ CLR) > .NET Class Library (VB.NET), where ">" represents a function call.
My VB.NET DLL just takes a value and returns it back, keeping it simple for now. In the end, this will do some more advanced stuff that makes use of some .NET functionality.
Public Class TestClass
Public Function TestFunction(ByVal param As Integer) As Integer
Return param
End Function
End Class
My Tcl Extension (C++ CLR) creates an object of the type above
int TestCmd(ClientData data, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[])
{
// Check the number of arguments
[code].....
If my VB.NET DLL is in the same directory as my extension DLL, the extension crashes when it instantiates a TestClass object. I've noticed if the VB.NET DLL is relocated to C:Tclin, the extension will find it, and TestCmd can be called just fine. The problem is that this will eventually need to be deployed across a number of PCs, and it's preferred not to mingle my application's files with another application's.