I am trying to get the value of a dropdownlist and post it to the viewstate and I am encountering this error:Object reference not set to an instance of an object. Description:An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Source Error: Line 142: 'Mimick the DropDownList Lin 143: Dim ddl As DropDownList = CType(ctrl, DropD
[code].....
When I place a breakpoint on that line and add a watch it says the value is "Referenced object has a value of 'Nothing'"How can I check for a value of nothing? I thought that is what the IsNothing was for. I have tried Convert.ToString() and still the same result.
I have an object array that I want to reference. The object array is in a deep set of classes so it takes class1.class2.class3.class4 just to get to it. I need to use this many times throughout my code so I figured I'd just create an object i.e. Dim Obj as Object and reference this array:
Dim Obj as Object = Class1.Class2.Class3.Class4.ObjectsArray
Problem is I can't resize the referenced array, by using the reference. The following does not work:
Redim Obj(5)
How come it isn't referencing my object array completely? is it because its the same object type?
I am grabbing a DataTable from a database and am displaying it in a DataGridView. One of the columns in the DataTable is a Boolean, which is properly displayed as a check box column. This part is working fine. Now I want to put an optional filter on the DataGridView which does not show any of the rows that are checked. So I now have a DataView object that can filter the DataTable and have bound that to the DataGridView. Great!
Now the problem is when the user clicks the Check Box and then focuses another row (or anything else), the row that was just checked immediatly gets filtered. However I would like the row to remain visible until the user commits the changes to the data. Is there any way to get the a DataView to not filter rows that have been modified?
I have a dataview object that is being populated by database fields - so I can sort on these partulular columns by specifying the actual column names without any difficulty. However, I have been asked to add a few more columns to the dataview, and these columns will be calculated columns, not directly derived from an underlying database column.The users want to be able to sort on these new columns as well - even though there is no actual column name I can use to sort.
I have not been able to see where I can sort a dataview based on the actual column integer value used when the user clicks the appropriate heading to sort.
If want to do a DataView.Find on a DataTable that is already 'ORDERED' by the Column I am seaching, so a DataView.SORT should not be necessary, but it throws an Exception if I don't give a .sort command before the .find command. Is there any way to avoid this apparant duplication ? and speed up the search time. Its a very large table - 1 million rows. I am using VB 2010
I got a problem with dataview that get data from datatabel (Col1 : ID,Col2: Time) and I'm sorting by Time in desc ... when the values for example {40.21,80.21,70.25,25.2} the dataview sorting them as I need but when one of values goes above 100 for example {40.21,80.21,100.25,25.2} the dataview always sort the highest number is the buttom, I don't know why ..
This is a sample code
Dim dt As New DataTable dt.Columns.Add("ID") dt.Columns.Add("Time") [CODE]...
I am looking for an advice how to do a drag and drop copying an object anywhere on the form and also move an object around and place it where the user wants. Is that possible? Kind of something what we have in the designer of Visual Studio, we can drag and drop a label or a textbox down on the form.
I have a copying error with my program. I am trying to copy the internet cache folder, and the error states that some files cannont be copied (read only maybe?) How can i make it copy, or just skip the uncopyable files?
I have a class named State that stores a lot of data regarding the current state (status) of the program (like the user's name, has he saved his work, last color he was using, etc). Before I allow the user to reset the state of the program, I want to backup the entire contents of State in case the user changes his mind and wants to undo things back to the way they were. I'm not looking for a complete undo algorithm, just a way to copy the contents of one object to another object (of the same class).
After reading through several forums, which suggested that I should add a referenced DLL (whose source cod I have) to solution as an added project, I am unable to step through the code of the referenced DLL that generates an error. I also turned off"Enable just my code" from Tools->Options-> Debugging. However, I am still not able to step into the referenced DLL's code I added the pdb file and the referenced dll to the bin/Debug folder of the original code that I am working on
I created a standard exe project and then an Activex exe.I compiled the activex exe and tried to make a project reference to the activex exe and keep getting the error ... can not be referenced because its project type is exe
I have a VB project that has a referenced to other project in the same Solution. I want to use Type.GetType() in order to obtain a type object from the referenced project but the method keeps returning Nothing.[code]...
Is the any way I can embed a referenced .dll as an embedded resource? Basically so I just have 1 file on compiling, rather than a EXE and a .dll. I've tried ILMerge, but it doesn't support WPF assemblies.
If I try to call my extension method which is defined like this:
Module LinqExtensions <System.Runtime.CompilerServices.Extension()> _ Public Function ToSortableBindingList(Of TSource)(ByVal source As IEnumerable(Of TSource))
As per [URL] How can I achieve this? 'processPacketVB' is a 'variable' but is used like a 'method' is the error I'm getting with these references to the project and class and function.
using VBProcessPacket; namespace UIST { public partial class FormActionMenu : Form { private void timerDelay_Tick(object sender, EventArgs e) { VBProcessPacket.ProcessRX processPacketVB = new VBProcessPacket.ProcessRX(); //read the receive buffer as a string RXpacket = processPacketVB("test"); // processPacketVB throws the error 'processPacketVB' is a 'variable' but is used like a 'method'
I have the following projects: TradingProject (my code) Has reference to TradingLibrary, and to ApiLibrary? TradingLibrary (my code) Has reference to ApiLibrary ApiLibrary (3rd party code)
I'm making several projects (like TradingProject) that communicate with a software through use of an existing ApiLibrary. But I want to push generic methods into a library I write: TradingLibrary.
Still, I would like to use some parts of the ApiLibrary directly from TradingProject. However, I then would need to pass an object (of an ApiLibrary class) into a method in TradingLibrary. Where the object should be recognized. However I assume this will be a problem, as TradingLibrary use it's own reference to ApiLibrary, so it will not be recognized as the same classes? Is there some way I can "forward" the ApiLibrary reference from TradingLibrary to MyProject, such that they will use the same reference? Or do I need to duplicate the classes and inherit from ApiLibrary for each class? Like:
NameSpace TradingLibrary Public Class SomeClass Inherits ApiLibrary.SomeClass End Class
I guess that would work, if I do it for all classes I need, but is there perhaps some simpler way I'm not aware of?
I'm co-developing a vehicle information system that reads and presents data from a communication bus. Signaling information on the bus is stored on some kind of database (from the dark ages i'd guess) from which it's only possible to get data out of by extracting a xml-snapshot. Since that wasn't bad enough, someone in upper management thought it was a great idea to treat different parts of the system as different projects (it looked really nice in the organizational chart) which lead to more databases...It is now my responsibility to merge these xml-files into one and before I start banging my head against the wall i thought it would be a good idea to check with you geniuses if there's any neat solution to my problem.The structure of the xml is somewhat like this:
I have been using Excel in vb.net for years and no problem but I have a new app and nothing is working. First I can't get Microsoft.office.interop referenced anywhere, which was weird. Then I can't instantiate Excel App.. Dim pExcel_App as New Excel.Application -- this gives me error "New cannot be used on an interface??But I can do this..Dim pExcel_App As New Excel._ExcelApplication -- where did this come from?Then I can't put anything into cells Dim wkbSheet As Excel.Worksheet wkbSheet.Cells(1,1) = "Title" --- this give me an error "Expression is a value and therefore cannot be the target of an assignment"
THe really weird thing is that I have an old app open at the same time that is just fine with all this code. AND the intellisense is different for each cell.The good one sets is as a range, the bad one says it is an object???I re-installed the MS PIA's but this didn't help.
I decided it was about time I learned about accessing Microsoft Office products via VB.NET. I started with Excel and it all worked fine, I could create a new Excel Application, open a workbook from file and read from the sheet then close it all down again no worries. However, when I turned to Word...things got strange. Using the code provided below, every time I run it an instance of Microsoft Word opens itself on the desktop (with no loaded content). I didn't have this problem when using Excel with similar code, so I have to ask..what gives? Is there a way I can stop MS word opening at all? At the moment it just flickers for a second (it opens when I open the document, then when I call the Quit method it shuts down a split second later)[code]...
I would like to enumerate an assembly's referenced assemblies and determine what should or should not possibly be included as a dependency in deploy scenarios.For obvious reasons I would want to exclude those assemblies that would be included by the CLR install.Is there any way to track back an assembly to being part of the default install of the CLR?
I have a project which contains all custom controls and images; we'll call it projectBase.Now I have created a windows forms project (project1) that references projectBase. I need to access the embedded resource (images) of projectBase in project
I am wanting to make a class that can be referenced in from other applications. In this class I simply want to do a showdialog to a form. That form has a ssrs pre-defined within it and a viewer all set to show the report. But when I try and define that action I get that my form is now declaired
Imports System Imports System.Drawing Imports System.Collections
I have a Button and a Picturebox control on my mainform. How can i code the mainform so that when the start btton is clicked it displays the file "student.gif" on the picturebox. The picture is added as a refrence to the project..[code]
Everything worked great this morning on my ASP project. Suddenly, I have 48 errors. Similar to the following: Name 'pnlVars' is not declared 'txtPolicyNo' is not a member of 'LetterWriterASP.UW' Seems every control I reference is now no longer declared or not a member of my project. I checked the page, the controls are all there with the same names & IDs.