Determine A Row That Has Violated Database Integrity?
Aug 5, 2008
I would like to determine which DataGridViewRow causes an SQLException to occur.A typical scenario follows:1) Using LinQ, I select a set of 'StockItems' as a datasource for a datagridview, and all works fine.2) I insert a new object and (purposely) leave a primary key value blank.3) I attempt to save using MyDBContext.SubmitChanges(Data.Linq.ConflictMode.FailOnFirstConflict)4) An SQLException is received.How do I tell which row has caused a violation, particularly when one or several changes have been made. I would like to advise the user that a specific row in the datagrid caused the error to occur.
I have an MS Access database and an MS Visual Basic 2008 front end.I get this error when trying to update a record that has related records:The record cannot be deleted or changed because table 'X' includes related records.I only want to update one field in the row in the 'parent' table which is not the primary key field of either record but the 'Update' command seems to want to rewrite the whole datarow. Rewriting the whole row causes the error (as this updates the primary key). If I switch off refrential integrity checking in the underlying database this solves the problem except that I want to maintain referential integrity so its not really a solution. I have tried beginEdit and EndEdit with no success - same error.Is there a way to update just one field in a row and write that back to the database?
If I was to upload one or more file(s) to a server, is there anyway to check that / those file(s) against the file(s) stored on my computer without downloading the file(s) to check against the original file(s)using VB.Net?This would need to be done in a recursive fashion from a parent folder downwards, the folder being of the end-users choosing.
Is it possible for my application to check if its been modified?
e.g. Could i compile the app and use a 3rd party tool to calculate the MD5 checksum of the compiled exe - and inside the app, code it so that if the MD5 checksum doesnt match then run the deactivation process?
I know its not foolproof but if it makes it slightly more hassle to crack my app i'd rather have it
How to ensure data integrity in multiple table update (which have relationship like reference of a column)[code]Now when I update the tables in datagridview in win form .and update it using dataadapter .update then how to make sure that all the data is updated correctly.
I'm using VB 2010 Express with a local Access DB. I am having trouble determing whether there are changes in a DataGridView to save back to the underlying DB.
The DB has been copied to the project directory and its properties (by selecting it in the Solution Explorer) include Copy to Output Directory: Copy Always, so I know that any changes I make when running a build will disappear on the next build. The problem I'm having is within a run / test session, working with the application.
The Access database has the following connection string, with Application scope:
I've searched the forums but never seems to find an answer for this one.. I recently connected to MySQL database server "Automatically" in Visual Studio 2010. I want to know if there's a way to determine the connection state for "Automatically created" connections in Visual Studio 2010. I know how to do it for"programmatically created" connections but just want to know how on the auto-generated ones.
I want to filter the SQL Compact Database to get rows that as been synchronized to the SQL SEVER Using sync framework can any one give me an hint on how to get this done. I will prefer a sample code in VB.NET
i havea dropdwonlsit (loads on the page_load event) and a unbound CheckBoxList is based on the selection from DropDownlist, the checkboxList is display CheckBox (might be one or two or three or any numbers)..... i just want to know after the page is loaded on the browser and user click on the checkbox's, i need a way to know what checkboxs users have selected... what is the best way of doing that? so far i have come up with this...
I have a need to figure out which adapter is used when a connection is created. In other words, if I have multiple NIC cards (i.e. wireless, lan, etc) on my machine, which card is being used for the connection?
I'm intend to use Aero glass in my program. It require use Black background to use this. If user is using Basic style, it will be very bad :( (although there's no error). How can I know if user is using Aero?What is big but light?
Does anyone know of a way to detect recent activity in a VB.net windows forms application?
We have a retail store where users share floor computers, the application will be on each machine and require a log in before use. I am trying to find a way to automatically close the application if it has been idle for lets say 10 minutes.
I guess I could do something similar with the current windows log on session - set a gp that logs the user out after 10 minutes of inactivity - but if there is an easy, non memory intensive way to do it in vb.net i would rather use that method
In VB6 if I wanted to see if a datetime field wasn't set, I could do something like if myDate = 0 then. I tried that with VB.NET and it can't compare to an integer. How do we do this now? I found the Ticks property, so if myDate.Ticks = 0 does seem to work, but I'm not sure if that's the "right" way to do it. None of the other things I've tried have been successful.
Dim dt As New DateTime If dt.Ticks = 0 Then MsgBox("dt.Ticks = 0") 'this fires If IsDBNull(dt) Then MsgBox("IsDBNull(dt)") 'doesn't fire, so no good If Not IsDate(dt) Then MsgBox("Not IsDate(dt)") 'doesn't fire, so no good 'If dt Is Nothing Then MsgBox("dt is nothing") 'not legal syntax
I want to hook the keyboard and make some actions (in vb.net) when a specific physical key is pressed.I have found online several excellent keyboard hook dlls, but there is a problem: the hook dlls find the keycode of the pressed keys, not what physical key is pressed.So, for example, in a USA keyboard if I press the key on the left of the Right-Shif key I see the e.keycode: 191 (OemQuestion), in a italian keyboard I see the e.keycode 189 (OemMinus).This means that if I put in My.Settings the code "189", an italian user can see that has to press the key I want, an USA user see another key to press to have the same action because on it keyboard the OemMinus key is not on the left of the Right-Shift key.now the question is: how to determine univocally the keyboard keys? What do I have to put in My.Settings that determinate a specific physical key, the same for all the keyboard languages?
I'm trying to determine in vb if a URL is absolute or relative. I'm sure there has to be some library that can do this but I'm not sure which. Basically I need to be able to analyze a string such as 'relative/path' and
Public Class A Private aa As Integer Dim bb As Integer Public cc As Integer
[code]....
what is the size of the object oA?and what if Class A and B contain methods?(I meant the size of object)what if inherited class B contains overridden methods?(size of object)what if inherited class B contains variables with same name as in Class A?(size of object)I need theoretical answer. Does those access specifiers Private,Dim,Public make any difference in allocating memory because of their different scopes?On what basis memory is allotted for a method? etc.
Screen.PrimaryScreen doesn't always work because on a multi-monitor setup the user may move his/her taskbar to a screen other than the primary. Finding the screen with minimum working area doesn't work too because there may be monitors with different resolutions.
I have a VB.NET windows application in which I'm using Outlook's contacts as my address book to get a list of email addresses. I'd like it to use Outlook as the address book, but if an Outlook mailbox has not been set up or there are no contacts then I don't want Outlook to come up at all. The problem that I'm having is as soon as I try to access Outlook the Outlook Startup Wizard comes up, which I don't want to happen. Here is my code:
Dim ao As Outlook.Application Dim ons As Outlook.NameSpace Dim Contacts As Outlook.Items
I'm a little foggy on System.Type versus an actual class type (like Object or XmlDocument) in .NET... will this code correctly determine if the type of a particular object is equal to a class I specify?
// Given "myObject" (unknown type), and some class type (let's say "MyClass")...
If myObject.GetType.Equals(MyClass)
If TypeOf(myObject) Is MyClass[code].....
Which one is correct? Bonus points if you can provide some information on what a class identifier is versus what a System.Type is. :)
Note: The language doesn't matter here, VB.NET or C# is fine, the code above is pseudocode.
I got the following error but am perplexed why .NET thinks this DLL is located in the internet zone when clearly it is on the Intranet.
Here is the error NUNIT is throwing:
Unhandled Exception: System.TypeInitializationException: The type initializer for 'NUnit.ConsoleRunner.Runner' threw an exception. ---> System.Security.SecurityException: That assembly does not allow partially trusted callers.
I am having hard time determining how to get 1st, 2nd, and 3rd place determined by time. I was thinking about bubble sort through an array, but since I am determining lowest to highest based on numbers = runner it just sounds more confusing. The code to determine second is not that efficient, I know there is an easier way. That is the part where I am stuck.
Public Class Form1 Private Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
