I have a third party dll. I wish to create a variable to reference to one of the variable in it.so that the value in the class change, my value also change. The senario can be reproduce from the code below.For the code below i wish to get the form to display 2 instead of 1. How can i make my variable test2 always referencing test.testValue?
View 11 Replies
Variable 'loNode' is used before it has been assigned a value. A null reference exception could result at runtime.
why I am getting this error?
Imports System.Xml
Module Module1
Sub Main()
Dim doc As New XmlDocument
[code].....
Does anyone know of a good 3rd party reference for Win32 API for .Net where VB.Net is the target language Most API references target C as the language of choice. Frankly, I hate C and all C like languages.
View 11 RepliesDo i need to add a reference to a third party control(DLL) before i can use it.When i go to project->add refernece ,i select the control but it didn't becomeavailable in toolbox to use it.Do i need to install that control?I just placed it inwindows/system32 dir.
View 6 RepliesI am using Umbraco (a .NET CMS), and it has a reference to a specific version of a DLL (see 1 Umbraco Reference below). This is fine until I try to hook into the .NET MailChimp API which references a different vesion of the same DLL (see 2 PerceptiveMCAPI below).I can think of a couple of options for resolving this
a. Get either the Umbraco or PerceptiveMCAPI source and reference the same version of the DLL, really do not want to do this for compatibility reasons
b. Dump the 2 DLLs in the GAC, I want to avoid this as I see deployment issues arising if someone forgets (I know we should have an automated deployment but time is restricted)
I remember that there is a third option to specify what version of the DLL to use in the configuration. Is this possible and what is the code for it?
1 Umbraco Reference
// Assembly Reference CookComputing.XmlRpcV2
Version: 2.4.0.0
Name: CookComputing.XmlRpcV2, Version=2.4.0.0, Culture=neutral, PublicKeyToken=a7d6e17aa302004d
[code]....
I pass this class i created a variable by reference and i want that reference to be assigned to m_Text so that when i change m_Text it changes the TextValue variable i passed. Example:
Dim test2 as String = "ok"
Dim test as New GeneTextBox(test2)
'then some one changes the text in the GeneTextBox and i want it to change the test2 string...
Public Class GeneTextBox
Inherits Windows.Forms.TextBox
Private m_Text As String
Public Sub New(ByRef TextValue As String)
[code]....
I have the following code passing a dataView variable to a function and I am getting the following warning:"Variable 'cl' is passed by reference before it has been assigned a value. A null reference exception could result at runtime."
Function Editclass()
Dim cl As DataView
Bindclass (SqlConnection2, cl)
[code].....
The code below works for the class that I hard coded "XCCustomers" in my RetrieveIDandName method where I use CType. However, I would like to be able to pass in various classes and property names to get the integer and string LIST returned. For example, in my code below, I would like to also pass in "XCEmployees" to my RetrieveIDandName method. I feel so close... I was hoping someone knew how to use CType where I can pass in the class name as a string variable.
Note, all the other examples I have seen and tried fail because we are using Option Strict On which disallows late binding. That is why I need to use CType.I also studied the "Activator.CreateInstance" code examples to try to get the class reference instance by string name but I was unable to get CType to work with that.When I use obj.GetType.Name or obj.GetType.FullName in place of the "XCCustomers" in CType(obj, XCCustomers)(i)I get the error "Type 'obj.GetType.Name' is not defined" or "Type 'obj.GetType.FullName' is not defined"
'+++++++++++++++++++++++++++++++
Imports DataLaasXC.Business
Imports DataLaasXC.Utilities
[code]....
I'm writing an application for a device running Windows XP. There are 2 versions of the device and each version has its own API to communicate with the device's software. The application I'm writing needs to pull the same data from the API. My question is how to write a application that will detect at runtime which version of the device it is on and use the appropriate API.
I've created an interface containing all of the common methods and also classes for each device that implement the interface. Now I need to know how to activate the correct one at runtime.
Public Interface IAPI
Sub InitializeMachine()
Function GetActiveProgram() As String
[Code]....
I want to add a Reference to my application in run-time mode and i want to list the public keys of this Reference in run-time mode I'm using VS2005.net Windows XP professional
View 6 RepliesI need to reference a .net .dll file at runtime of my program.Does anyone know the code to do it?
View 3 RepliesI'm using the following code to reference an embedded resource at runtime (it's a DLL that I can't package with my app for policy reasons). I need to add a second resource and do the same exact thing.
Private Sub MyApplication_Startup(ByVal sender As Object, ByVal e As Microsoft.VisualBasic.ApplicationServices.StartupEventArgs) Handles Me.Startup
AddHandler AppDomain.CurrentDomain.AssemblyResolve, New
[Code]....
I created a .net assembly, which works perfectly if I create before runtime. But i'd like to know if it's possible to reference at runtime. The reason is because i'm creating an application which will be used in several servers, and it will be reference that same .net assembly, but the .dll file will be in different location per server. I know that when I reference before runtime, the .net assembly it will be pointing to is from the original (or at least that's what I think).
View 2 RepliesBeen searching a trying examples for a couple of days and always fall back to the "null reference" error on this one. I have a set of instructions coming from a SQL database and the number of instructions is a variable. Therefore, I have a TabControl which I add TabPages to at RunTime depending on the number of instructions there are. The TabPages are then created with the names; Step1, Step2, Step3, etc.Each TabPage is made with the same controls and all of the controls are named the same from page to page (e.g. "instr" is the name of a TextBox control that exists on every TabPage).I can successfully create a GetControl method that will return the correct TabPage, but I cannot reference any controls on that TabPage.I can only change properties of the TabPage.If I try to reference a specific control on that TabPage, like the "instr" TextBox control, I get the null reference error.[code]
View 9 RepliesIs there a way to change reference at runtime ? I am automating Word from VB.Net. I think what I have coded will be same for both Word2003 and Word2007. I used Word 12 Object Library reference(which is of Word2007). So, I want to know how to make it compatible with a machine installed with Office2003. That is, it will check the whether the machine has 2003 installed. If so, use that reference. Otherwise use 2007.
[Code]...
I get a warning message that reads " Variable 'cust' is used before it has been assigned a value. A null reference exception could result at run time.", but it occurs in my vb file "Northwind.vb with the following code:
Public Class Northwind
Private cust As BizObjects1.Customer
Private Sub frmCustomer_Load( _
ByVal sender As System.Object, _
ByVal e As System.EventArgs) _
Handles MyBase.Load
[Code] .....
Warnings: Variable 'targetPath' is used before it has been assigned a value. A null reference exception could result at runtime.
View 39 RepliesCustomerStreamToRead' is used before it has been assigned a value. A null reference exception could result at runtime.I get that warning once I commented out the streamreader line listed below. The warning shows for the line loading settings(z). The app runs but I don't like warnings in my error list.
Code:
Public Sub LoadSettings()
Dim Z As Integer
Dim CustomerStreamToRead As StreamReader
[code]....
Due to this error I am getting a default date 1/1/1900. Variable 'dr' and 'dr1' is used before it has been assigned a value. Here's the code:-
[Code]...
im using many variables in my project however, they are most of the time used for 1 or 2 things, so having them loaded up like that forever sounds not very good for performance.Is there a way i can remove a variable after i no longer need it?
for example:
private sub button1_click() handles button1.click
dim result as integer = var2 + var1 / 2
[code]....
I'm trying to populate some file dependant settings from the database. Values I can add no problem but how to set the names as they differ from datafile to datafile?
For Each myRow In SetModDataTbl.Rows
Dim SettingName As String = myRow.Item(1)
Dim SettingValue As String = myRow.Item(2)
'>> SettingName = SettingValue <<
Next myRow
I am upgrading a very large project from VB6 to VS2008. I have several forms with dozens of combo boxes on each form. I use the same combo box names for each form and want to fill them from a module with different items depending upon the calling form. In VB6, I dimensioned a public variable - FormName as object and called Set FormName = frmMyForm1 on Form Load. In a module, I was able to write the following code:
With FormName
.combobox1.additem("item")
.combobox2.additem("item"
End With
I cannot make this work in VB.Net. When the form loads I call FormName = Me. If I dimension Friend FormName as Object, I get the error message that Public member combobox1 on type MyForm1 not found. If you are attempting to access members on a late-bound object make sure it is declared public". If I dimension Friend FormName as Form, I get an error that says "combobox1 is not a member of System.Windows.Forms.Form".
I have tried both CType and DirectCast to convert the form variable from Object to Form with no success. I also tried creating a public array and storing each form name in it.
I am working on a little program (game) is called Pig latin. I created a sub procedure and I passed the word to be converted by value and the piglatin word byref.Now when I call the procedure in the button click event I get the wavy green line under the variable passed by reference but the program works ok. Call Convert_to_Pig_Latin(strOriginalWord, trPigLatinThe error message when I hover my mouse over the green line says " Variable strPigLatin' is passed by reference before it has been assigned a value. A null reference exception could result at runtime."
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[code].....
In Visual Studio 2010 is it possible to check the state of variables during run time. When a run time error occurs the error is highlighted and you are able to mouse over different variables to see their values when the error happened. I would like to do something similar except without the error.
View 7 RepliesI am trying to create a number of objects depending on the width of a row of an array, is there a way I can change the name of the variable being Dim 'd as I don't know how wide the array will be.
I have been trying something along the lines of:
pseudocode
For x as integer = 0 to UBound(MyArray,2)
Dim Object & CStr(x) As Object Type
Next
global variable can be created during runtime?
View 1 RepliesI'm multiplying X*Y*Z in a loop of 200 interations Y is declared as a constant. A timer can cause the loop to pause for 10 seconds.
During this 10 sexond pause I would like to change the value of Y. It needs to be changed only for this run, not a permanent change which can be done in the declaration.
Class1:
Dim v as integer
public sub storeVar(byval s as integer)
v = s
end sub
[code].....
I need to save a reference of variable s in Class2 in variable v in Class1.(i.e. when the value of s changes v also changes (and vice versa)Is this possible since vb.net doesn't have pointers?Will it work if I change "byval" to "byref"?
Such as:
mylist.FindAll(Function(item) item.property = variable)
The reason I ask is if I use syntax like this, I tend to get a string to whatevever conversion error, which makes me think "variable" is being treated literally as a string.
I have a class that I would like to link at construction to a given control (say a textbox)
I know I can put a variable into a subroutine referentially but is there a way to store it in the same capacity?
