I have a program that is accessing many similar tables using a linq to sql datacontext. Do linq to sql tables implement a common interface? I would like to write methods that could work with any of the similar tables, so it would be great to do something like
Dim myTable as ILinqDataTable
If switch = "TableA" then myTable=myDataContext.TableA Else myTable=myDataContext.TableB
[Code]...
I know there are similar questions on stackoverflow - and I looked through them and think my issue is somewhat similar, but haven't been able to find a solution by looking at any of these other questions/answers.I'm getting the error when attempting to execute the following code:
Private Sub btnReserve_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnReserve.Click
' Check that the room is still available.
Dim dbCheckOccupants As New pbu_housingEntities
Dim hall As String = CStr(Session("hall"))
[code]....
It is catching an error on this line:
Dim myID As String = GetID.First.id.ToString
As far as I can tell I'm not using multiple contexts?
I have 3 table which are Timetable, Schedule and Consultation slot and I wish to combine them so that all the data are able to retrieve easily.
Timetable are having
1. TimetableID
2. Lecture ID
3. ClassVenue
4. ClassStartTime
5. ClassEndTime
Schedule
1. ScheduleID
2. LectureID
3. ScheduleVenue
4. ScheduleStartTime
5. ScheduleEndTime
Consultation Slot
1. ConsultationID
2. LectureID
3. StudentID
4. ScheduleID
5. remark
Here is my code in metadata
Partial Public Class CombinationOfTSC
<Key()> _
Public Property LectureID() As String
Get
Return m_LectureID
[Code] .....
I'm having error at c.LectureID = s.LectureID = t.LectureID
I wish to get the combination of 3 tables through the lectureID since there are lecture ID on 3 tables.
I have been trying for days now how to create a process to the user to easily create a connection to any installed data types they have installed. I have found an example right inside vb2008. I never use this because I code my own connections, but this would be real nice if I could include it or duplicate it.
View 1 RepliesI have to forms, form1 and form 2. On form1 I have datagridview with all the fields in it. If I double click on it I would like a new form to open where I can add a new record.
Then I have a edit button on the form, If I click the edit button I would like another form to open where I can edit the data in.
In this post it explains it, I need the same but for linq to sql.
[URL]
I'm in the process of moving from ADO.NET to Linq. The application is a directory search program to look people up. The users are allowed to type the search criteria into a single textbox. They can separate each term with a space, or wrap a phrase in quotes such as "park place" to indicate that it is one term.
Behind the scenes the data comes from a XML file that has about 90,000 records in it and is about 65 megs. I load the data into a DataTable and then use the .Select method with a SQL query to perform the searches. The query I pass is built from the search terms the user passed. I split the string from the textbox into an array using a regular expression that will split everything into a separate element that has a space in it. However if there are quotes around a phrase, that becomes it's own element in the array. I then end up with a single dimension array with x number of elements, which I iterate over to build a long query.
I then build the search expression below:
query = query & _
"((userid LIKE '" & tempstr & "%') OR " & _
"(nickname LIKE '" & tempstr & "%') OR " & _
[Code]....
I have the following code:
Private Sub btnReserve_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnReserve.Click
Using dbContext As pbu_housingEntities = New pbu_housingEntities
[Code].....
executes it always get 0, because the row has not yet been created in the database. I can just move this last bit of code out into its own Context, but is there a better way to do this?
how do i remove the contents of an array element such that if
hello(0) = "hello"
hello(1) = "hello123"
hello(2) = "hello123123"
i want the result to be
hello(0)="hello123"
hello(1) = "hello123123"
First I dont know how to "link" forms easily. For example: Form1 is like a calculator and I get value X (label.text). How can I "sent" that X to form2? I mean like: Form2.label1.text = form1.label1.text but it doesnt work like that. And I know why it doesnt work.. I dont know how to save that X. Every time I close and open again Form1 I had to start over. So how to save and link forms? Then another: what's wrong with this? Or how I could make it another way? Textbox2 should be numeral (should I code something for it?) and user can set it's value. Now it doesnt show anything in label5. [code]
View 6 RepliesI'm facing a problem regarding multiple inheritance in VB.net:As far as I know VB.net does not support multiple inheritance in general but you can reach a kind of multiple inheritance by working with interfaces (using "Implements" instead of "Inherits"):
Public Class ClassName
Implements BaseInterface1, BaseInterface2
End Class
That works fine for classes but I'd like to have an interface inheriting some base interfaces. Something like that:
[Code]...
I downloaded a .net component that I would like to make consumable by COM clients. This component allows one to create a DXF file (Cad drawing). The problem is that the component is composed of quite a few class files, some inherit another. All the examples I found only show one file no namespaces etc. [Code]
View 1 Repliesis there a way to create an interface of delegates? Sub dostuff(byval arg1 as dele1)works, problem is that i have 8 delegates, so i will have to give it 8 signatures. that isn't so bad, but the problem is that when there are various combinations of signatures it gets real real bad.
Sub dostuff(byval arg1 as [Delegate])works, but it allows me to accept delegates beyond the 8 that i wanted (it's like declarign arguments with base Object)could i be able to do this:
Sub dostuff(byval arg1 as Idele1to8)
I am trying to set-up a mutiple choice test and I only want the questions to show up on one form and not multiple forms. How do I do this? I want the user to answer the questions and then click a continue button and the next question will appear on the same form.
View 9 RepliesI always have a problem with dynamically generating WHERE conditions to a SQL statement which are base on the nformation given by user (combobox, listbox, checkbox etc.) Here`s an example of how I normally deal with the problem:
[Code]...
I m trying to understand Interfaces so that I can implement them in my programs but I m not able to imagine how should i use them.Also give me some eg of using them with multiple inheritance in C#
View 9 RepliesI'm working on a small app that takes a series of screenshots to analyze a graph. The problem I'm having is that, on my 3-monitor setup, the screenshot works fine on the primary monitor, but when I drag my app to either of the other monitors, the screenshot is black. I've also tried taking screenshots of the other monitors while the app is in the primary monitor by feeding the coordinates into the CopyFromScreen call directly, and that works, but as soon as I drag my app to one of the other monitors, all my screenshots are black. Also, and I'm pretty sure this will be important later, my primary monitor is attached to the on-board video, whereas the other two are attached to a separate video card. Both the on-board and installed cards are ATI Radeons.
Here's the screenshot code I'm using:
Code:
Namespace ScreenShot
'/ Provides functions to capture the screen, in whole or part
Public Class ScreenCapture
[code]....
I have multiple bitmaps(i) in arrays, and I want to know if I can save each of these bitmaps into on animated gif file. I thought about using image.saveadd() but i'm not sure if that will work.
View 2 RepliesI have a strange problem; on my form there is a TabControl, and every tab contains a DataGridView.I set all DataGridViews Autosize column property to DataGridViewAutoSizeColumnsMode.Fill and then I set for every column the width with FillWeight, using the same set of values for every DataGridView.Although all these DataGridViews should look the same, the one on the first TAB looks different, it looks like I used different FillWeight values.All others DataGridViews on subsequent tabs looks the same, only the one on the first tab looks different..
View 2 RepliesHow to work with multiple combobox. I have several combobox. I it to have same itemlist and set a default value for this.I used to do:
Code:
Dim MyItemToBox(3) as System.Object
For i as integer = 0 to 3
MyItemToBox(i) = "A" & i
Next
[code].....
I'm dealing a problem in implementing interface for multiple class.
Assuming I have a class named Class Unu .
I created an interface called Test for those 2 classes.
The first class Unu has 2 data members(i=12 and j=12.17). When you run the program it stores the result on screen 24.17
The second class called Doi has 2 data members(a=20 and b=32.17).
What I want now is to do the same thing for data members a and b so that it stores on screen 20+32.17=52.17
My problem is that I want to be displayed also the result for the 2 data members for the second class on my screen. I implemented the interface on class Doi but I cannot see why he isn't displaying me the second result 52.17.
What I must add to my code to do that?
Here's the full code:
CODE:
i doing asp.net and using vb.net.I have a datalist control which inside it show a product img, description, price the problem is that i was to show the product another img, so i want to have a small picture below the img, so when click on the picture the img change to another.
i want something similar to this link : [URL]..this link they use flash to come out with the effect that i want, but they are not in datalist, so think that i may need to use ajax but which one?anyone have any sample or example ? if i was to use the jquery easy slider numeric navigation how am i going to implement onto the datalist?
Basically, we have three databases to grab data from. One is a SQL Server database, one is an Access database (which is particularly annoying to connect to because we have to map a network drive and such), and the final one will be an Oracle database when IT finally gives us rights.I'm thinking about creating a helper function that makes querying any one of these databases as easy as possible. I want to create a two-dimensional array
Dim myEasyResultArray(10,10) as String
myEasyResultArray = DatabaseHelper("Access", "SELECT * FROM Employee")
Is this a good design decision? Also, how can I have the array be the right size? Can I just do this?
Dim myEasyResultArray = DatabaseHelper("Access", "SELECT * FROM Employee")
Should this be a module or a class? I don't really need to share variables?
I want to create a VB program for my final year project,the contents of which can be editable by the user, for example when new information becomes availabe it can be easily added. Now,I thought that this could be done using the text box, although it doesn't seem to be possible.
I plan to use a database to hold the initial information.Could I achieve program 'updatability' in a fairly easy manner?
I don't know the best way to use multiple forms in VB, but I have created a problem and I'm not sure where it came from or how to fix it.
Background: I start the program at Sub Main. This is the main function:
Code:
Module modFunctions
Dim frmD As frmDAQ
Dim frmT As frmTrendView
[Code].....
it works, but I don't want to have to change the entire project.
insert images in a combobox. I understood the code, but what I'm asking is how do I add multiple images per line of the combobox?? I mean the way, the smileys are displayed in dropdown grid in Yahoo! messenger or the sort when you click on the smiley button..
I'm using Microsoft Visual Basic 2008 Express Edition with .NET Framework 3.5
I have an access database with 5 tables.I want to fill a dataset with the entire contents of the database.Why can't it roughly look like this?[code]Instead I'm having to create an adapter for EVERY table, tab the table name (why?), fill the schema, and then fill the table.
View 1 RepliesI need to make basically a bunch of 2d arrays, that I can access the independant values easily. Like multiple properties As an example:
[code]...
Because later I have to access Value1 in a manner that spells out each independantly. I have used some basic Structures to define 1 property and does something with it. But not 2 properties, and I am out of my norm on creating a Class to do something like this.
How to implement an observer pattern in VB.NET?
Currently I have a lot of working code in VB6 which the company wants me to migrate to VB.NET. Well, that would normally be straightforward ... yes? Unfortunately, not so in our case.... recently, our company decided that I need to modify it to implement the MVC (Model View Controller) paradigm to make it truly OOP and adaptable to TDD (Test Driven Development).
Currently, my move was to start with a simple one, opening a form and then grabbing a piece of text from a textfile and putting it as the caption of the form... now, that is easy.
The problem lies in trying to implement observer patterns ... in the observer pattern I cannot simply call the usual me.caption = mytextstream.ReadLine from the form_load event instead, I need to use objects that would use an interface to register themselves as observers as the form loads but not necessary having to be residing in the form_load event... in fact ... if there is somehow a way for me to make such a thing happen before the code goes through the form_load event then that would more completely separate the View layer from the controller layer which gets implemented through the use of observers and observer related patterns.
I have a linq union statement that has been giving me some trouble and I can't see where the issue is.The error is....All queries combined using a UNION, INTERSECT or EXCEPT operator must have an equal number of expressions in their target lists.
I know the error means that I am selecting different amounts of elements in one of the linq statements, but I've examined this query extensively and I haven't been able to see that as the issue.
[Code]...
I am trying to pass several search parameters to an LINQ expression to retrieve all entries that contain one of the search items.
Example:
Dim query = From p In db.BEW_PROFIL
For Each searchItem As String In searchItems
[code].....