VS 2010 Null In Array?
Aug 23, 2011I've done arrays before but,
For x = 1 To 5
Dim canvas(x) As ShapeContainer
Dim cell(x) As RectangleShape
[code].....
ADVERTISEMENT
Null Reference Exception Unhandled Error When Input Is Saved Into Array After Array Has Been Erased?
Jun 23, 2011n my project i am to enter a name and a test mark into two separate text boxes and then select the button to store the information into the arrays, one array for names and another for marks, but when it is reset using the Erase <Array> fuction andi try to re enter information, no matter what information is entered i get a "Null Reference Exception Unhandled" Error.I am using Visual Basic 2008.My code is as it says from now:
Public Class frmAdverageTestMarkCalculator
Dim ClosingMsg As String
Dim Closingtitle As String
[code].....
Null Value From Database And Jagged Array
Feb 12, 2012I need to scan database and insert its values into an array. But I'm having some difficulties in handling null values and array.
The database looks like this:
0 1 2 3 4
30 31 32
33 34
36 37 38 39 40
38 39 47 48
I want to make array rr_item which gonna looks like this:
arr_item(1)={0,1,2,3,4}
arr_item(2)={30,31,32}
arr_item(3)={33,34}
arr_item(4)={36,37,38,39,40}
arr_item(5)={38,39,47,48}
Every code I've tried result in error everytime I tried to insert null value into any kind of c=variable, including array which I want to use. And I'm not quite sure with what I'm doing in jagged array I want to build.
sql_list = "SELECT * FROM retail"
oledbCnn = New OleDbConnection(connetionString)
Try
oledbCnn.Open()
[Code] .....
How To Remove Null Characters From Byte Array
Jan 13, 2011bytes ( 00 00 00 ) I'm trying to remove from a specific set of locations within a byte stream. The following code is what I'm using. I tried using the Trim function as listed in the code at the bottom but that had no effect. I'm extracting from a fixed byte range and there are null values after the end of valid ascii characters. Dim temp() As Byte = GetByteArray(FrameData, 3, 32)
Private Function GetByteArray(ByVal MyArray As System.Array, ByVal Start As Integer, ByVal Length As Integer) As Byte()
[Code]...
Assign Data To An Array From A Text Box - Null Reference?
Apr 24, 2011when i try to assign data to an array from a text box, i get a null reference exception, stating "Object reference not set to an instance of an object".
View 5 RepliesNull Reference Exception While Trying To Initialise An Integer Array?
May 15, 2011I am getting System.NullReferenceException:Object reference not set to an instance of an objectwhile executing the below code..!!
Dim arr() As Integer
Dim g,j As Integer
g=10
[code]....
Resize Array By Removing All Empty/null/0 Elements?
Jun 2, 2012I have a large one dimensional array that is called ArrayHold which is populated at runtime. I run a loop to scan through the array to find out which elements need to be removed based on a few parameters. This all works great, now I am left with two arrays. The original one and a new one which contains the locations of the elements to be removed.
Original Array: ("A")("B")("C")("D")("E")("F")("G")("H")
Second Array with index/count of elements that needs to be removed: ("0")("3")("5")("7")
End result should be preferably not in a new array but a "ReDim" of the original array:("B")("C")("E")("G")
What would be the simplest way to achieve this? I could run a loop to make all the elements that need to be removed "0" or ""? Would there be an easy way of resizing and array by dropping/removing all the white space or empty elements?
Office Automation :: Null Reference Exception On A Byte Array
Dec 28, 2011I've converted an application for connecting to a vpn server and starting a remote desktop connection from vb6 to vb.net. But now when I'm trying to run the program I get an ArgumentNullException I've tried searching for a solution but I've been unable to find one. Below is my code:
[Code]...
VS 2010 : Copy This Array To A Temp Array So That The Temp Array Has All The Same Values As The Original Custom Array?
Jun 19, 2011I have an array of people stored in a custom structure array... how can i copy this array to a temp array so that the temp array has all the same values as the original custom array?
View 4 RepliesGetting Error In Code As Initially Array List Is Null / NullReferenceException Was Unhandled
Oct 19, 2009The code below is used to check if the application setting, an arraylist is populated or not via the count method.
When running the program fails with error "NullReferenceException was unhandled" as initially the setting (arraylist) will contain no values.In similar circumstances I would declare a new instance of the object or set value to string.empty or check if DBNull.
I know application settings have a save method but to reference/load them one is not needed.I also left the value field in the projects -> settings to be empty.[code]...
Use A Null Value In A Double In 2010?
Jan 3, 2012Straightforward question: I have a few variables that are doubles. I would like to be able to store a "null" state in them, i.e. I need to be able to represent that the variable doesn't contain valid data. I'd really rather not associate a boolean "is valid" variable with every single double
View 2 RepliesVS 2010 Null Value In A Datareader?
Jun 30, 2011im using this bit of code to recieve data from a database. problem is if one off the values in the databass is null it kicks up an error how can i handle this so in the event of a null value it gives a "" string value
[Code]...
VS 2010 Null Values
Nov 10, 2011I'm confused at the variety of different ways to say "null" in VB.net. I've got text and numerical fields with checkboxes to mark unknown values; I just want to populate a table with the fields' values (if the corresponding checkbox is not checked) or null values (if checked) so I can later input them into a mySQL database.So my question is just which of the various null types I should be using in what situations.
View 6 RepliesVS 2010 SQL Select With Null Value?
Jan 28, 2012I want to select all records in a table and only 1 field in 2 related tables so my query is:
strSQL = "SELECT CL.Name, CL.FirstName, T1.Description, T2.Description " & _
" FROM Clients CL, Table1 T1, Table2 T2 " & _
" WHERE CL.Tab1Cod = T1.Code " & _
" AND CL.Tab2Cod = T2.Code"
All works and all records are selected only if fields CL.Tab1Cod and CL.Tab2Cod contain data but if one or both contain NULL value then NO record are selected. how can I test in a query statement if a filed contains a null value and, in this case do not expose the related field ?For example if CL.Tab2Cod is null the field T2.Description will be empty but all other fields are exposed.
VS 2010 DataGridView Selected Row Null?
Feb 16, 2011I am trying to pull data from a cell in the currently selected row in a DataGridView control. I fill the control with data from a SQL database through a dataset.I am trying to retrieve the index of the currently selected row so that I can pull the data out of the first cell in that row. Here is the code I currently have:
Dim i As Integer i = dgvSchedule.CurrentRow.Index MsgBox(dgvSchedule.Item(0, i).Value)Seems pretty simple to me, but for some reason I am receiving a "NullReferenceException, Object reference not set to an instance of an object" error on the second line.
VS 2010 Designer Error 'Value Cannot Be Null'
Apr 3, 2012I just made a bunch of changes to my program, so I can't just undo what I did. My main form gives me the following error every time I try to load the designer:
Warning1Value cannot be null.
Parameter name: objectType
I have rebuild the project with no success. A few other posts have mentioned that there could possibly be a reference to a button or image that no longer exists, but I have no idea which one.
Also, I don't really know what the information below means, but it shows up on the error page under 'call stack', so I figured I would include it
at System.ComponentModel.TypeDescriptor.TypeDescriptionNode.GetRuntimeType(Type objectType)
at System.ComponentModel.TypeDescriptionProvider.GetRuntimeType(Type reflectionType)
[Code].....
VS 2010 LINQ Null Return?
Dec 2, 2011I'm having trouble figuring out what to do with the bolded part, when there are no nodes to return.If there are no image tags inside the <images> tag, i get an "Object reference is not set to an instance of an object".I have been searching and searching for an answer but can't find one.
Dim orders = From o In xmlLinq.Descendants("order")
Select New With { _
.orderID = o.Attribute("id").Value, _
[code].....
VS 2010 Null And Zero Length Strings?
Mar 14, 2011This is related to my last question.Even though Access considers Nulls and zero-length strings (ZLS) separate values, often developers wish to treat them as equivalent for the sake of an If...Then statement or some other stretch of code. One way to accomplish this is to write code like this:
' Not so efficient
If IsNull(varAge) or varAge = "" Then
' do something
[code].....
VS 2010 Null Reference Exception
Feb 4, 2011i keep getting this null reference exception error and i can't figure out what i need to do to fix it. I have this in the form
[Code]...
VS 2010 Null Reference Exception?
Mar 18, 2012keep getting this null reference exception error and i can't figure out what i need to do to fix it.I have this in the form
Private Sub cbLookUp_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cbLookUp.Click
Dim webDownload As New Net.WebClient
[code].....
VS 2010 Showing Null Dates In A DGV
Jul 21, 2010I've got a DataGridView that has a column that will show dates/times this column needs to be sortable so I use this to tell the DGV that it is storing Date type objects (so that sorting works fine automatically):[code]Now the problem is that there will be some records shown in this DGV that do not have a value for this date column. How can I display this? If I dont set a value for that column or I set it to Nothing then the cell just shows the minimum date value (01/01/1601).Oh and this DGV is not using data binding if that makes any difference. Perhaps this might be a good time for me to investigate this data binding lark though if that will help with this issue? I'm sure I recall seeing something about being able to use one value but display another value when you use data binding thats all.
View 6 RepliesVS 2010 Check DGV Cell For Null Or Empty Value?
Feb 29, 2012I have the following code that checks if the value in a cell contains a nummeric value.
Private Sub dgvOrderRegel_CellValidating(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellValidatingEventArgs) Handles dgvOrderRegel.CellValidating
Select Case e.ColumnIndex
Case 4 'Aantal
If Not IsNumeric(e.FormattedValue) Then
[Code]...
VS 2010 Function Null Refernce Exception?
Jun 16, 2009.i'm having a slight problem with the following function i wrote
Dim bytes As Byte()
bytes = Convert.FromBase64String(Base64String)
However, it returns me System.OutOfMemoryException error when the Base64String contain large
[code]....
VS 2010 Handle Null Dates In A Database?
Apr 18, 2011I am reading dates from a table in a database to display in a DataGridView column that is formatted as a date. The problem is that when the value is null in the database my program errors out because it cant convert the value to a date. How do you guys handle this? *Edit: If I set the value of my date variable to "Nothing" it displays as "1/1/0001" in my DataGridView, and I would like the cell to be empty for the null dates.
View 24 RepliesVS 2010 Null Reference Exception With Image
May 3, 2012I've got a little problem. I'm trying to choose a background for the program based on Settings, but I'm getting a Null Reference Exception and I don't know what I'm doing wrong. Here's the
[Code]...
VS 2010 String.Length() Returns Null
Jun 11, 2011[Code]...
By my logic, this should only assign .length to index IF the length of strItem is longer than 0. This check is there in case the listbox is empty, or the user has not selected an item. However, everytime I go through this code without an item selected I get:
[Code]...
VS 2010 Unique DataColumn With Several NULL-values?
Jan 17, 2011I'm using MySQL to store some numbers. One of the columns in the database is defined as unique, but it does allow multiple NULL-values. That is exactly how I want it.ut when I'm trying to load the data into my strongly typed DataSet, I get a error saying that a constraint fails... I do understand why that happens (several rows with NULL-values in a unique column), but is it a way to keep a DataColumn in vb.net unique, but still allow several rows with NULL-values like in MySQL?
View 2 RepliesVS 2010 Doesn't Trim Get Rid Of Null Bytes In String?
Jun 17, 2010I'm receiving a byte array from a network device by using the TcpClient class and as I have no idea how much data will be being sent I have to just declare a buffer that is X number of bytes long and keep reading into that until I've got all of the data. I then convert this byte array to a string using Text.Encoding.ASCII.GetString but the problem is that this gets any null bytes that were at the end of the buffer after the string and it includes them in the string. This then means when I do String.EndsWith it doesnt work as I would expect it to because there are just loads of 0 bytes at the end of the string.
Once I had realised that was what was happening (which took a long time as these null bytes are completely invisible when you are looking at the data in String form) I thought fine I'll just use Trim on the string but I've found that this doesnt make any difference at all. I thought Trim was supposed to remove any blank space from the start/end of a string, which I assumed would include empty bytes as well.
So is there any alternative I can use that will trim the empty bytes off the end or do I have to do it the 'manual' way and loop through my byte array before converting it to string and remove any null bytes? One thing that has just popped into my head as I'm typing this is to try using the Chr method and pass it 0 and combine that with Trim like so:
VS 2010 Reading Excel Returns Some Rows As Null
Oct 25, 2011I have a vb.net app that I can read a .xls file into a dataset or loop through as oledbdatareader and it gives the same result.Some of the rows have all nulls when I loop through them but if I open the same file in Microsoft Excel I can see that row fine.[code]From the info above the first two SKU values would come through fine but when I get to the 3rd row it would show a null.Is it possible that it kind of inherits the first rows type and since the 3rd row isn't all numeric if nulls it? [code]
View 1 RepliesVS 2010 Remove Null / Unused Arrays From A Program?
Sep 19, 2011How to remove unused arrays from a program? The array is has an upper bound of 19. If the array isn't full, I get a null array error.
View 9 Replies