is it possible to create typed data set tables dynamically or modify columns and the data types of an existing table. what i'm trying to achieve is to read the sqlString from an external file and populate a typed dataset table in order to use it as a crystal report data source.
View 3 RepliesI am using VS2008 and SQLite. I have created a database and several tables and am attempting to populate the tables with data from arrays.
The following code (example) works fine but stops after it inserts 30 to 50 records. I am running the VB code in debug mode and when it stops, I press pause to see where it is. It stops on "SQLcommand.ExecuteNonQuery()" and when I press continue (F5) it will insert another 30 to 50 records.
I do not get an error message. Is this a timeout issue? How do I keep the loop running to the end of the array?
Following is example code.
Dim
SQLconnect As New SQLite.SQLiteConnection()
Dim SQLcommand As SQLiteCommand
CODE:.....................
I have used VB (versions 2 - 6) through many years; however, I am crash-course training myself into the VB2008 / VB2010 world kicking a screaming. I would like suggestions as to what SQL database access method should I focus more on in my learning process without making me feel that I'm a million years behind. I know I have WinForms where I can create a datasourse and drag / drop fields or tables on a form to create a grid (not really what I'm looking for).
My trouble isn't so much designing the form but in how I access the database. Theres XML, LINQ to SQL, ADO.NET, and many other methods. Not only do I need to grasp these methods quickly but I also need to know what type of projects I should create. What I mean is...I was thinking that I would design a WinForm app; however, I see that there are WPF apps and others to chose from. This is getting deep. I know it depends on the project that I'm working on. My plans are to write an app based off of either an SQL Express 2008 or SQL Server 2008 database. This first app will be standalone for now but may later become multi-user. I know I'm far behind on my learning curve coming from VB6. I have read a bit on VB2005 / 2008 / 2010. I own
both VB2008 and VB2010. I use VB2008 at work. I know ADO.NET is still alive but by what I read online, it's a dying method and is only kept for backward compatibility. XML and LINQ to SQL and other methods are all pretty new to me.
I created a typed dataset and my database guys are constantly updating and adding columns to tables.. is there a way to do a comparison
View 1 RepliesI'm looking for a the shortest/aseist way in VB.NET (or C# but using VB.NET at the moment) to get the string value of a method's name dynamically given the method call.For instance, I have a class like this:
Public Class Blah
Public Sub Foo()
End Sub
End Class
Now Foo is a strongly-typed cover for a dynamic setting and I have an event handler that will fire when the setting changes and return the string name of the setting that changed.
I'd like to be able to switch/select on this string and have a case based on the Foo() method. To do this I need to able to get the string name of the Foo method from the method call itself (i.e. somehow GetMethodName(blahInstance.Foo())).
I have a SQL Server database for which I have created a strongly-typed DataSet (using the DataSet Designer in Visual Studio 2008), so all the adapters and select commands and whatnot were created for me by the wizard.
It's a small database with largely static data, so I would like to pull the contents of this DB in its entirety into my application at startup, and then grab individual pieces of data as needed using LINQ. Rather than hard-code each adapter Fill call, I would like to see if there is a way to automate this (possibly via Reflection). [code]...
In a typical session with the program I'm writing, the user needs to be able to access the data in 1 to 500 (maybe) tables (but always only one table at a time). Up to now I've been creating these single table datasets dynamically, as and when required.I've now come across the distinction between typed and untyped datasets (where typed seems to be the recommended option). It seems, though, that typed datasets are created at design time only and not dynamically. Is this correct? Are all of my dynamically created datasets therefore untyped?
View 12 RepliesI've been into programming, I've landed a job with a local company, the entire project the gentleman is paying me to do is incredibly easy, with one hitch, the original project I'm converting is built using access databases, for efficiency, and easier online transfer, I'm wanting to switch to using an SQL database, I've got plenty of experience inserting, modifying, and controlling an access database, but where should I start to learn how to essentially set up, create tables, and modify data within an SQL database?
View 5 RepliesPlease anybody help about how to create two dynamic combo box. Like Country and province.. when I select country conutry Combo box then Province Combo box automatically show same country province.[code]
View 5 RepliesAdmin users can add HTML content to a website via a CMS textbox control.
When this content is displayed to a website visitor, I'd like to identify the presence of a HTML table (added by a Admin user using the CMS) and display an option for visitors to export that table.
I can handle the exporting, but identifying the HTML tables has me stumped.
I am working on a CMS system for my business, and need to be able to generate notifications dynamically into a control panel. Please note, I am using .NET 2.0, coding with VB and my data is all held on a MySQL database.This is pretty simple for most aspects, but as the whole thing is dynamic some things are proving more difficult.I have a set of tags which are dynamically generated with a repeater as follows:
<asp:Repeater runat="server" ID="locationRepeater">
<ItemTemplate>
<p id='locationNotification' title="<%# Container.DataItem %>" runat='server'>
COUNT DATA NEEDS TO GO HERE
</p>
[Code]...
The data is really, really, simple, all I need to be able to do is query a table on my MySQL database for COUNT of ID WHERE locationName = Container.DataItem during each loop of the repeater... but I don't know how to do this.I'm thinking maybe I have to do this first, create a table in memory somehow, but I am afraid I have no idea how to achieve this.
Has anyone got any examples of a similar thing, it's kind of binding to a repeater from two datasources... each task is very simple, but I don't know how to put it all together!
I am using the ASP.NET MVC VB.NET XML Literals View Engine created by Dmitry Robsman and described on his blog in this post.
[URL]
I would like to create strongly typed view pages using this view engine, but it doesn't seem to contain the requisite VbView(Of TModel) generic type by which I would create such a view class.
The end result should look something like this:
Namespace Views.Client
Public Class Details(Of Models.Client)
Inherits SiteMaster
[Code]....
Once there is a VbView(Of TModel) class that inherits from Dmitry's VbView class, how to hook that up so that it works with standard MVC controllers that call the view like this.
Function Details(ByVal id As Integer) As ActionResult
Dim c = SomeGetClientFunction(id)
Return View(c)
End Function
I have an application in VB/C# .NET which needs to interact with a third party API, but I would like to interface it out so I can use a mock API for testing purposes.[code]...
View 2 RepliesI created a dataset in Visual Studio 2010 containing two tables: tblCategories and tblAnswers. tblCategories has two columns: CategoryNumber (AutoNumber and primary key) and CategoryName. tblAnswers has three columns: AnswerNumber (AutoNumber and primary key), Answer, and CategoryNumber. The CategoryNumber columns in each table are related. I have a command button which I want to use to add a record to the CategoryName column in tblCategories with the data typed in a textbox. When I try to access the dataset to add a new row(dataset.tblCategoriesDataTable.NewRow), the NewRow method isn't present. I've done some reading which suggests that I need a TableAdapter, but it seems like that is for connecting to an external file because I have to select a connection. I have no external SQL files or database. I want the user to be able to create a database within my program.
View 1 RepliesI have 1 text box and 1 button. I want to save the data typed into the text box to the sql database I have connected to my software. How do I code it it?Mick
View 5 Repliesi'm using a strongly-typed dataset and i created a table adapter with a query and i previewed the data and it works fine but when i run the application it can't fill the table with this query and it throws an exception that it violates a constraint orkeyFailed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints.
System.Data.ConstraintException was unhandled
Message=Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints.
[code].....
I have a combo box that contains data from a database.I am using autocomplete to assist users in finding the large amount of data that the combo box is bound to.What I need to do is check the typed data with the values bound to the box.I need to show a message box if what the user types isn't in the list. Right now if its not in the list and they tab out of the box it throws an exception.Is there a way to validate what is typed with the data in the list. I tried changing the drop down style to dropdownlist but this doesn't allow the user to type in data.
View 3 RepliesLet's say I have an edit view that is strongly-typed to a table called "MyData". The view has multiple tabs, each with several different fields from the table. For performance, the data is only loaded when the tab is viewed, so if you only edit a field on tab 1 and submit the form, the data for tab 2 will not be loaded.
The problem I'm running into is on the submit. I'm doing the typical routine of finding the existing record in the database and updating the passed values:
<AcceptVerbs(HttpVerbs.Post)> _
Function Edit(ByVal data As MyData) As ActionResult
Using dc = New MyDataContext
[Code].....
However, this method doesn't know which tabs were loaded, so if the tab with "desc" on it is not loaded, this method thinks the user blanked out the "desc" field, and sends NULL to the database.
How can I construct this so that only loaded fields are sent to the database, and unloaded fields are ignored?
I used to build data layer by using Classes, however someone suggest to use Strongly Typed DataSets because it's faster in development. The data layer that I'm going to build should support multi DBMS(Oracle,MSSQL, MySQL..)
View 3 RepliesI used to build data layer by using Classes, however someone suggest to use Strongly Typed DataSets because it's faster in development. The data layer that I'm going to build should support multi DBMS(Oracle,MSSQL, MySQL..).
how is better build it by using Strongly Typed DataSets or by using Classes?
I am designing a form to Enter new City Name list where i accept following fields
CityName, District, State, Country, Pin.
because a State names and Country names can be retrived from earlier entries, i want to allow user to select desired name from a list in combo box or a list in Auto Complete Custom Source for text box, to do this i have added a Table Adapter to underlying DataSet having Query "SELECT DISTICT STATE FROM CITY ORDER BY STATE".
Now, how do i use this Table Adapter to fill the ComboBox List without binding
And also Custom Source List for TextBox.
I have this lambda expression Me.SubcriperGrd.ItemsSource source.Where(Function(p As subscripers) p.Navn Like navn)
where i should filter the grid data based on the typed input in a txtbox
It returns the result when i type the full name but it doesn't filter the data as i type along in the txt field
I need to consume data from a webservice. I am receiving xml data and using this to create objects through property setters.
In one particular case, an attribute of the object (called "is_active" and indicates whether the object is active or inactive in the application) is represented sometimes by
<field type="BooleanField" name="is_active">1</field>
and at other times by <field type="BooleanField" name="is_active">True</field>
The client code requires me to represent this using integers 1 and 0. The returned string "True" or "False" results in System.FormatException, as expected.
What is the most graceful way to deal with this situation?
I'm trying to do a LINQ Query against a typed datatable that will return me duplicated data.With out going into too much detail, here's the basic setup:
strCode1 - string type
intCode1 - int32 type
intAdjustor - int32
There are more fields but these are the ones that are important.I'm going to do my best to describe this, as it's kind of confusing.In theory intCode1 is a key for strCode1 (hence the names). So each time intCode1 is duplicated, the same strCode1 should appear. Example:
[code]...
Ultimately I'd like to get a List(Of T) - where T is my typed data row. In SQL, I would simply use a sub query, to get a distinct list of strCode1 and intCode1, then do a count, grouped by strCode1 where I get more than one row.I'm not sure how to translate that into LINQ, AND get the original types data rows returned in a list.
I have a situation where I have an xml document that has a bunch of elements that I basically use as data variables. I populate the variables from various sources and then transform the xml file to an html file for user viewing.having to remember the names of all the data elements in the file is somewhat tedious. Is there a way to generate a strongly typed xml document object so that one can simply dot into the various data elements?
View 5 RepliesI signed up for a free 30 of Azure. I logged in, created a database. I am able to connect (=Test Connectivity). But that's it. I don't see anyway to create tables, etc. Also how can I connect this db to vb.net (I am using vs.net 2010)?
View 3 RepliesI would like to know the best, or standard, way to accomplish real-time client updates in a small multi-user application using an access data table as a data source.Specifically, this application will be used by 3-4 people. It uses a datatable which is filled on form load and bound to a datagrid at design time. The datatable is stored on a shared drive. The data table on the shared drive is updated in two ways:
1) Users can update the datagrid which then updates the datatable on the shared drive via the data adapter's Update method.
2) A server application does some work on some text files, periodically updating the data table.
I need the clients to reflect the changes to the data table on the shared drive as closely to real-time as possible. I know that the data table stored in memory on the client is disconnected from the data table on the shared drive, so I must query again to get the updates.
1) Is there an alternvative model I can use which is connected, and which will automatically reflect the updates in the data table on the shared drive?
2) If not, what is the best way to check for changes in the data table (so I can know when to call the data adapter fill method)? I am planning to poll the drive for a change to the .mdb file, raise an event and then fill the data adapter when the event is triggered. I am using this method successfully now to check for changes to a text file in another application, and I know how to implement it?
I would like to know the best, or standard, way to accomplish real-time client updates in a small multi-user application using an access data table as a data source.
Specifically, this application will be used by 3-4 people. It uses a datatable which is filled on form load and bound to a datagrid at design time. The datatable is stored on a shared drive. The data table on the shared drive is updated in two ways:
1) Users can update the datagrid which then updates the datatable on the shared drive via the data adapter's Update method.
2) A server application does some work on some text files, periodically updating the data table.
I need the clients to reflect the changes to the data table on the shared drive as closely to real-time as possible. I know that the data table stored in memory on the client is disconnected from the data table on the shared drive, so I must query again to get the updates.
I have two questions:
1) Is there an alternvative model I can use which is connected, and which will automatically reflect the updates in the data table on the shared drive?
2) If not, what is the best way to check for changes in the data table (so I can know when to call the data adapter fill method)? I am planning to poll the drive for a change to the .mdb file, raise an event and then fill the data adapter when the event is triggered. I am using this method successfully now to check for changes to a text file in another application, and I know how to implement it
I have two data tables within my data set that are loaded onto my form on form_load using statements written in code (not the designer. When I change a value for the first table via a text box the change is made to the data set. But when I try the same for the second table, the change doesn't remain in the data set when I switch to a different company and come back. I query the second table using the primary key of the first table but no code is needed when I change the values for the first table so I don't understand why the same doesn't work for the second when I change a value via a data-bound text box....
Here is my code that initially binds the data:
'This is used to read our data from the data base
Public Sub Read_Data_SQL()
Call Clear_Bindings()
[CODE]...
Here is the code I call when the selected index of my company combo box changes to have the second table reflect that of the first:
'This sub populates any information contained in the Contact2 table
Private Sub Update_Contact_2()
Dim Company As String = cmbCompany.Text.Replace("'", "''")
[CODE]...
I want to split this up into 3 side by side tables but have been unsuccessful in any of my attempts. Currently it prints one large table. The reader.Read is performing a really simple query that pulls a few names from a table.
Dim htmlString As String = "<table>"
While reader.Read()
htmlString = htmlString + "<tr><td>" + reader(1) + " " + reader(4) + "</td></tr>"
End While
[code].....