I set up a test harness by checking for and then deleting records added to the db in the previous testing session, and then I test my recording adding code by adding back the same records.Interestingly this code works fine when there is a break in the debugger, but fails with a "duplicate key" exception when I let it run with no breaks, which leads me to believe there is some kind of concurrency issue
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I set up a test harness by checking for and then deleting records added to the db in the previous testing session, and then I test my recording adding code by adding back the same records.Interestingly this code works fine when there is a break in the debugger, but fails with a "duplicate key" exception when I let it run with no breaks, which leads me to believe there is some kind of concurrency issue.The basic metacode is as follows:
DoTest()
dim j as datacontext
dim recs = from myrecs in j.mythings select myrecs where myrecs.key="key1" or
myrecs.key = "key2"
[code]....
I've confirmed that I'm properly deleted the previous added records, and this works fine as does adding the new records when I have a break in the code before I hit the add records step. but without the break, it throws duplicate key exceptions in the "addrecordestomytable" method suggesting that it hasn't grabbed the current version of the table when it creates the new data context in addrecordstomytable, even though the records should have already been deleted.I've tried refreshing the table, but this doesn't seem to work either.Note backing database is ms sql server 10?
I have a data bound datagridview where I am allowed to add and delete rows.So a new row is the last row in the grid with the '*'. When a user starts to type in the new row, that row no longer is considered the new row. It is then inserted into a row above the new row (*). The user, however, can press 'Esc' key and this row gets deleted.If the user does not pressed 'Esc' but move the cursor along that row, this row will be permanently there. I have tested this scenario and check the underlying dataset and it registers no changes as in the myDataset.hasChanges=FALSE.If I call myDataAdapter.Update(myDataSet), nothing gets updated. How do I save this row to the database?
View 2 Replieshow to make linq2sql behave like my custom code used to, I want to check to make sure that it isn't already "built" in behavior that I can just use by setting up the relationships right in the designer...
Very simple example: I have two tables: Person and Notes, with a 1 to many relationship (1 Person, many notes), linked by Person.ID->Note.PersonID.
I have a stored procedure (all data access is done via SP's and I plan on continuing that) which makes the Link2SQL a bit more work for me.
sp_PersonGet(@ID int) which returns the person record and sp_PersonNotesGet(@PersonID) which returns a set of related notes for this person.So far so good, I have an object:
Dim myPerson As Person = db.PersonGet(pnID).Single
and I can access my fields: myPerson.Name, myPerson.Phone etc.and I can also do a
Dim myNotes As Notes = db.PersonNotesGet(pnID)
to get a set of notes and I can iterate thru this list like:
For Each N As Note In myNotes
( do something)
Next[code].....
Basically, Linq2SQl would need to call 2 stored procedures each time a Person record is created...Is this doable "out of the box", or is this something I need to code around for myself?
I have this one line property
Public ReadOnly Property DateToUniversal(ByVal dt As Nullable(Of Date)) As String
Get
Return If(dt.HasValue, dt.Value.ToString("u").Substring(0, 10), "")
[code].....
I want to use Linq2Sql as the data source for my Crystal reports. I have all my data in my domain objects in the form of Lists. The problem is all my domain model resides in a different namespace in the form of a .dll. And when i try to assign a data source for my report in Database Expert window, under .NET Objects, i can only see classes that are available in the current project and not from other projects in my solution, nor from other namespaces.
View 1 RepliesI have a timer that I've established that I have set to run at a 20ms interval.Within that timer code, I have some code that is performing a visual display, moving a graphic incrementally.This all works great on a nice fast machine, when I can be sure that the "work" is actually being completed before it's "called" again by the timer.It does not behave well on a slower machine, when I suspect that the timer is being called again before the work is being done from the previous call(s).
I've tried establishing a global boolean variable called "Timer1Active". I set this variable when I enter the code to TRUE, and to FALSE as I exit the procedure. I also check, using an IF statement if it is true at the beginning of the procedure, skipping all of the procedure if it's not yet been set back to false.This approach seems to stop the visual portion from happening altogether. I think, anyway. That or it's now way faster and I can't see it at all (but I doubt it).
I've got a very simple data structure. I'm using SQLExpress with Linq2SQL and vb.net
**ParentClass**
parentId
name
[code].....
I have tried to set up combo boxes in the gridview but all the combo boxes have the same value in them instead of the value from the database. I am using entity framework and WPF. There is a parent child relationship between two tables but the source for the combo box is a separate table with names and IDs for tags. I have been looking all day. Hopefully this won't be too easy to solve.
The "Tag" Column displays the combo box. The Column "Tag ID" displays the value from the database. When I display the data the TagID Changes in diffrent rows but the Tag column is the same (the first choice) in all the rows. When I change one combo box they all change. I can't see where they are hooked together.
Here is the XAML
<Window x:Class="MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="372" Width="675" mc:Ignorable="d"
[Code].....
What I can do: Display an image (e.g. a bitmap) by loading it into a control (e.g. picture box), showing that picture box (visible equals true / refresh) and then hiding it (visible equals false / refresh).The onset of the image onto the screen is not necessarily synchronized with the raster scan (needs to run on CRT monitor) meaning the lower portion of the image may appear one (partial) frame before the upper portion. Though I can specify (roughly) how long the image is on the screen I cannot specify the number of frames and there is enough variability in the timing that I will not get the same number of frames every time.
What I'd like to do: I'd like to be able to have my display wait until the beginning of the next frame before showing my image. I'd also like to tell it exactly how many frames to show the image before removing it. Ideally I'd like to be able to cue up multiple images to be shown for one frame each in order (animation).
I've found a lot of information on the web about DirectX but the few tutorials I've tried are overly complicated for my needs and invariably fail to start for unspecified reasons.I don't need 3D.What I want to display would work just fine in a picture box if the timing were cleaner and predictable.
I am using an activeX control to read data from an external source. This data is processed in 5 second increments. Each piece of data is passed through an event. When the event triggers I call a "decision" procedure from the event to process the data and make decisions on what to do, i.e. call other procedures, store the data, etc... This works fine when I have a small number of samples (around 10), however, when the number of samples increases to say 100, that is I am recieving 100 pieces of data every 5 seconds, the "decision" procedure does not fully run. Is it possible that the event trigger is causing the code to exit the "decision" procedure prematurely? I know that the "Decision" procedure starts since I have written data from the beginning of the procedure but not the end of it. how to handle the rapid event triggers?
View 7 RepliesThe code I have is meant to be used during possible rapid mouse movement by the user. It is supposed to get the current location (works), move to specified location (works), mouse down(works), mouse up (works), then return the mouse to the old position. I added the delay because it seemed that it was having trouble registering the click if done too quickly. The problem I am having is that if the user is moving their mouse during the time the code is activated, their movement can throw the location of the mouse down or mouse up events off even with the added check routine I added.
'Get current mouse position
Dim MousePosX As Integer = Windows.Forms.Cursor.Position.X
Dim MousePosY As Integer = Windows.Forms.Cursor.Position.Y
Q = True
'Move mouse to Q Location and click
[Code] .....
[Code]...
How to create a LINQ query that allows the end user to choose a few months?
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
View 1 Replieswhat is the most robust method for adding a empty row (to select "nothing") to a ListBox?
Dim List = Enumerable.Repeat(New TABLE With {.Text = "", .ID = -1}, 1).AsQueryable().Union(From t In mainctx.TABLEs)
ddlMangelKategorie.DisplayMember = "Text"
ddlMangelKategorie.ValueMember = "ID"
ddlMangelKategorie.DataSource = List.ToList
But this has some drawbacks:wordy must explicit write the Type (TABLE in this case), so i cant wrap this in a function have not found an solution, which works with anonymous types I.e. if I add a From t In mainctx.TABLEs Select Text=col1, id=col2 to the query, this method does not work anymore.
(Currently using VB.NET 2010 Express) I'm trying to make a program, the main of which is file transfer. I'm trying to create a program that will keep files and folders synchronized across multiple client computers. I'm using a File system watcher to trigger events, and Using a simple System.Net.Sockets UDP client transfer (found via google) to transfer commands between it and itself on other computers.
Here's that code (this just sends from one textbox to another over the internet)
Imports System.Net.Sockets
Imports System.Net
Imports System.Text
Dim udpClient As New UdpClient(1024)
Dim RemoteIpEndPoint As New IPEndPoint(IPAddress.Any, 0)
[Code] .....
By this method, I can rename, move, or delete files. I want to implement file transfer, so that whenever a new file is created, or updated, my program will automatically transfer the file to the other computers and update them there.
Im trying to debug a troublesome Project. I downloaded and installed the Symbols from MS, set my Project to use the Folder where I installed them, etc. When I start Debugging, I can see at the bottom of my IDE window that it is loading Symbols at a rapid clip, until it gets to It stops, and I have tried waiting 15 minutes to no avail.
The file exists - D:Symbols
asapi32.pdb90DF78A27042428D99A8021F064506472
asapi32.pdb - 1.40 MB (1,469,440 bytes) - Created Wednesday, November 24, 2010, 12:25:44 PM
I just made a rapid file transfer form for my photos.In which I drag photos into a listview with my destination folder set.I assign each individual file transfer to a new thread. This works very fast as compared to the standard drag n' drop.
View 2 RepliesWhich one of these two do you suggest for writing simple windows form applications?Visual C++ is too complicated for my small to medium applications and the proccess of creating seems to be longer when compared with C# or VB.NET.
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