Avoiding Warning "variable X Is Used Before It Has Been Assigned A Value"
May 13, 2011
I have a VB.NET command line project in Visual Studio 2008. There's a point at which I need to parse through an arraylist and output the contents to a file name based on a value in the arraylist. As I'm interating through the arraylist, I don't want to open and close the streamwriter every time as it causes it to be very slow. Instead, I want to check to see if a value is same as a the previous iteration of the loop, and if so simply do another "writeline" to the streamwriter. See snippet below:
This program is for advertising ads and prices are determined by which radiobutton is selected.This program uses objects created from a class . I am getting a waring message that Variable 'ad' is used before it has been assigned a value. A null reference exception could result at runtime. the warning is at ad.size = 225.So how do I get the variable filled before used if it depends on which radiobutton is checked? [code]
I have the following code that I am using to parse out a test file. I am getting variable conversion error in Sub Main() when I assign file = Read(). The return value of Read() is a TextFieldParser type. How do I assign the proper variable type to "file" so I can write the output to a text file?
Function Read() Using MyReader As New FileIO.TextFieldParser("C:UsersColinDesktopParse_Me.txt") Dim currentRow As String
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)
From the MSDN Article I read I should be using the StringBuilder rather than concatenating a normal string.However I do not know why I get the following errer: "Variable 'ShowString' is used before it has been assigned a value. A null reference exception could result at runtime."
I am working with VS 2010 web VB 2010 asp.net..I am trying to read table data with the help of dataset.xsd..i create a loginDataSet.xsd and in index.aspx.vb web page i wrote this code [code] But it showing that abc variable is used before it has been assigned a value a null reference exception could result at the runtime .
I am using visual basic 2008How can i fix this problem:Warning1Variable 'bla' is used before it has been assigned a value. A null reference exception could result at runtime.
this is my first post I'm making a cheque book balance for my college assignment, which 1st form will record the data of the cheque (Cheque Number, Payee's Name & Cheque Amount) and this information would be stored to a .dat file. with the 2nd form will balance the Current balance in the account minus the cheque amount which has been stored in the .dat file and then will list it in a list box with the payee's name, cheque number, etc. I have used a module which is below:
I'm getting the error message "Variable 'WordCreated' is used before it has been assigned a value..."As such, VB is not even letting me assign a value to any slots in the array.
Dim WordCreated() As String WordCreated(0) = "Hello!" That's just a snippet of my code, when declaring the variables. The "Hello!" part has just
I declare: dim PS as powerstatus Then I type: MsgBox(PS.whatever) and then the PS is underlined with a green line with a message saying something like: variable PS has been used without being assigned a value. How can I assign PS a value so I can use it? I know that the msgbox code is probably wrong - I'm just using it as an example.
I am using vb.net 2003 for a stand alone windows program. I access an Access database file via Jet 4.0 and OleDbDataAdapter.
The program is like a "check book" for commercial fishermen to track their landings in relation to the amount of "quota" that they have been assigned. The program is structured so a fisherman can enter multiple boat names and track each one seperately. To work on a particular boats account, the fisherman would select a boat name from a drop down list. The boat name is then captured and assigned the string variable name of "xid" and in a Module have this code:Public xid As String
I have used the DataAdapter Configuration Wizard to setup the data connection and assign the DataAdapter and DataSet. I went into the code and manually entered a WHERE clause to filter the data for the selected boat. The proper syntax was an issue that I had a problem with earlier, but once I got that correct, the program worked fine. The code that works is below:
I used code below to run rollback but in catch block, a warning message said that thistransaction used before has being assigned a value. How to void it?
Dim thisConnection As New SqlConnection("server=(local)SQLEXPRESS;" & _ "integrated security=sspi;database=MyDatabase") Dim sql As String = "DELETE FROM Employee " & "WHERE ID = 10"
This code works well but somehow it is giving me a warning saying: "Variable 'str1' is used before it has been assigned a value. A null reference exception could result at runtime."How can I remove the warning.
Public Shared Function getAllColumnNames(ByVal tblname As String) As String() Dim com As New OleDbCommand Dim con As OleDbConnection Dim str1() As String Dim dtable1 As DataTable [Code] .....
i am using the following VB6 code and I get this error Variable 'osv' is used before it has been assigned a value in VB2010.I want to use this code/method for getting the version, I just want to fix this
Public Class Form1 Private Declare Function GetVersionEx Lib "kernel32" Alias "GetVersionExA" _ (lpVersionInformation As OSVERSIONINFO) As Long Private Structure OSVERSIONINFO Dim OSVSize As Integer
As i tried to describe inside the code there is a strange assignment problem: According to code why FF000010 could not be assigned to the variable and there became an "overflowException was unhandled" while data inputting into the integer value that i could not resolve the problem.
... MsgBox(Hex(AlphaMix(16, 255))) ... Private Function AlphaMix(ByVal pInteger As Integer, ByVal pAlpha As Long) As Integer
Following code sample should concatenate the value. Concatenated value has to be assigned to variable AlphaStr. But result is always null in the variable AlphaStr.
The basic question is can I assign a variable to represent a control? As an example which of 12 tickBoxes have been ticked. Is this possible with a for next loop?
I have a strange problem with a lazy load property in my class.[code]The problem i have is that when i create a new instance of the class the value of 'mMarksLoaded' is true however when i put a break point on this section of code, execution is never interrupted.Is it possible that the .net framework is accessing this property behind the scenes?
I get error "Variable 'retVal' is used before it has been assigned a value. A null reference exception could result at runtime." Here is my
Private Function JoinDomain() As Object Dim BungeOU As String = "OU=Computers" & ",OU=" & SitesCmboBx.Text & "O=Na.Dir.Bunge.Com" Dim args(4) As String 'Dim args2(2) As String
My program does not build because of the following error. I understand the part about a null value, to a degree, but the assigned value I'm not sure about. by clarifying it's meaning. To me, there's nothing obvious about why it's not working.
I'm in a beginner programming logic and technique class that also teaches us VB, and I'm working on a program that is to simulate total theater revenue, that asks for the number of tickets sold in a particular section and then displays the amount of sales generated from that section. It needs to validate that the total number of tickets sold is not over the maximum seating in that section.[code]
1) I have a warning that "Variable 'section' is used before it has been assigned a value. A null reference exception could result at runtime" in line 18.
2) Regardless of the changes I've made, I always end up getting "0" as my end result. I'm actually supposed to use the toString currency format function when getting my end result, but that was mixing me up so I figured I'd at least make sure the output is correct before I fix that part. I thought I was on the cusp of having this working but I think I'm confusing myself more and more the more I mess with it.
I am converting a VB6 program to VB express and am having a couple of problems. One of them is a problem with the variable "strEncTemp". I have the warning "Variable strEncTemp is used before it has been assigned a value", and I can't assign a value to this variable without creating issues. It also seems that a null value is being returned and the code produced by this routine is corrupt. This seems to be the last issue I have in converting the code. I tried setting it to 0 but it then shuts down the program with an error. This is the portion of code that has the warning and produces a null value. [Code]
Today I discovered that something I had assumed about VB.NET for many years was not true (worrying!). I assumed that a variable declared within a loop had a lifetime of the iteration it was declared in, but in fact it seems it has a lifetime of the whole procedure.[code]I had assumed an output of False, True, False, True but instead it is actually False, True, True, True..In C# the equivalent code would not compile as you would get a compile time error of Error "Use of unassigned local variable 'var1'".I realise there are many ways to fix this and that best practice would be to declare the variable outside of the loop and reset it at the beginning of every loop through.I find this behaviour so counter-intuitive to me that I would like at least a compile time warning in VB.NET when/if I do this. (I could also then set this on any projects I already have and get warning that would allow me to check that my assumptions aren't causing errors).Does anyone know how/if I can get this to generate a compile time warning in VB.NET? Am I the only one that finds this counter-intuitive?
Below is my entire code for trying to add some boolean values to a list box that are queried from a datatable called "Availability" and the value booRV which is my OleDbDatReader is "Nothing" at runtime. The error is: No value given for one or more required parameters. I assume this is all the items that are being queried, but i am not sure. Here is the code:
i wanted to ask how to make picturebox1 ,to which functions are already assigned, perform the same function as picturebox2 ,to which no functions are assigned.For example:I have already made picturebox1 and have assigned it alot of function like when play button is pressed then picturebox1.visible = true and when we press pause button picturebox1.visible = false. So now i decided to make a theme and have to remove the picturebox1 and want to allow the picturebox2 to havefunction of picturebox1.But when i disable the theme the function of picturebox1 should go back to picturebox1.
