I have the following structure
|-Table 1
|--PK IDT1
|--Name field
|-Table 2
|--PK ID
|--FK IDT1
|--Name field
I want to bind Table 1 to combobox1 and Table 2 to combobox2 so as when someone selects a value in combobox1, combobox2 populates with only the rows with the FK IDT1 value from combobox1. Is this possible with databinding or do I have to code it?
How to bind data from database to combobox of winform in VB.NET .
Database : MSSQL server managemant studio
Front End : Vb.net 2008
In the combo box binding,i need to put "Product_gid" in index and "Product_Name" in the value of combo box.How do i add an item "Select" in the 0'th position of Combo box,So that every time i opened the list of combo box,the 1st item will be "Select",other from database.
I'm trying to bind CheckedListbox's Cheched items to Combobox my code is given below
Private Sub chklColumns_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles chklColumns.SelectedIndexChanged
cmbSort.DataSource = chklColumns.CheckedItems
End Sub
whenever I check an item first time it loads one item to the Combobox, but when I select second item still I have single item in the Combo...
Short and simple question. In Winforms you can bind a dataview to a combobox or some other control by simply:
combobox.DataSource = dataview
combobox.DisplayMember = "Something"
In WPF I've generally done databinding using an ObservableCollection and edits to the xaml. Is there a way to quickly do it, like the above? Edit: This seems to be the simplest/quickest thing I can come up with, anything inherently wrong with it?
[Code]....
If I turn off automatic updating of a binding data source by setting DataSourceUpdateMode = Never and then use a button to update the whole lot (using binding.WriteValue), a problem occurs - Namely, only the first bound control's data source is updated. All other controls are reset back to the original values.This is because when the current object changes (as happens after the above WriteValue), if ControlUpdateMode = OnPropertyChange, then all the other controls re-read in the value from the data source.
One way is to derive a class from BindingSource and add a WriteAllValues method.This method does the following:
(1) For each Binding, save the ControlUpdateMode
(2) For each Binding, set ControlUpdateMode = Never
(3) For each Binding, call the WriteValue Method
(4) For each Binding, reset ControlUpdateMode to the saved value
(5) For each Binding, if ControlUpdateMode = OnPropertyChange, call the ReadValue method.
If working with your own classes, would implementing IEditableObject resolve the issue?In another control I'm working on, I implement my own binding. The way I get around the issue in that is with the following code. (I've put in the bare minimum, I hope you can follow it!):
Private Shared ControlDoingExplicitUpdate As MyCustomControl = Nothing
Private Sub UpdateDataSourceFromControl(ByVal item As Object, ByVal propertyName As String, ByVal value As Object)
Dim p As PropertyDescriptor = Me.props(propertyName)
[code]....
So, when UpdateDataSourceFromControl is called, all the CurrentItemChanged events will be called for all other controls in the same BindingSource. However, because ControlDoingExplicitUpdate is set, they will not re-read in the value from the data source unless they happen to be the control that did the updating.ControlDoingExplicitUpdate is set to Nothing after all these events have completed, so that normal service resumes.
I have three tables Tasks, Notes & CallTypes Each item in Tasks and Notes has a relationship to CallTypes and my form edits work fine. However: Notes only belong to tasks, and when i update the note record we will need to change the CallType for the Task as well as for the Note and they could both be different.
I have the Notes working fine, but i cannot update the tasks. I have created a databindng on to a form from the datasources window. All the notes fields are ok and are working I then add the calltype field from the tasks, draged from the data sources window (i dont want all of the tasks fields, just the calltype).
The code does not through up errors, but when i save the form it only updates the notes and not the tasks.
In a winforms application (VB, VS2008 SP1) i bound a checkbox field to a SQL Server 2005 BIT field. The databinding itself seems to work, there is this litte problem: user creates a new record and checks the checkbox, then the user decides to create a new record (without having saved the previous, so there are 2 new records to be submitted) and checks also the second.
[Code]...
I have a custom control with a bindable property:-
Private _Value As Object
<Bindable(True), ... > _
Public Property Value() As Object
Get
[code]....
Also, here, I'm adding a handler to the DataBindings.CollectionChanged event.This is the second place that I retrieve the type:-
Private Sub DataBindings_CollectionChanged(ByVal sender As Object, ByVal e As System.ComponentModel.CollectionChangeEventArgs)
If e.Action = CollectionChangeAction.Add Then
Dim b As Binding = DirectCast(e.Element, Binding)
[code]....
I need the first place, because the BindingContextChanged event is not fired until some time after InitializeComponent.The second place is needed if the binding field is programatically changed.Am I handling the correct events here, or is there a cleaner way to do it?
Note: My GetValueType method uses the CurrencyManager.GetItemProperties....etc, to retrieve the type.
I am developing a Windows Form Application against a SQL Server relational database. An example of the database schema is:
TableA
------------------
PK A_ID uniqueidentifier
A_NAME varchar(254)
[code]....
In the form I have a ComboBox (cboA_ID) to select the TableA record (DataSource = TableA, DisplayMember = A_NAME, ValueMember = A_ID) and a TabControl where controls on each tab are bound to fields in either TableB or TableC.My question is, is it possible to bind cboA_ID to TableB.A_ID and TableC.A_ID?This is my first database application so if there is a better way to do this I'm all ears. I have set everything up using the wizards in Visual Studio 2010, so I'm still not 100% familiar with what all the various TableAdapters and DataSets do.
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 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:.....................
have a datagridview containing 2 tables left joined, so that:table1 LEFT JOIN table 2 ON table1.id=table2.idI get an error whenever I try to edit my datagridview."invalidOperationException was unhandled by the user codeDynamic SQL generation is not supported against multiple base tables."The error points to this line:
da.FillSchema(dt, SchemaType.Mapped)
da.Update(dt) << This line
'da = dataadapter
[code].....
In my datagridview I was fill in using join tables (table1 = pr_employees, table2 = pr_employee_deduction). My problem now is during save button I want to update records from table2 only.[code]
View 3 RepliesWe are presently developing an application, let's call it APP1, which uses a SQL Database which have about 800 stored procedures, 600 tables, etc. APP1 was originally created in order to replace another application, APP0, from which we do not have source code but only SQL tables, Stored Procedures, views, etc. Previous programers of APP1 used some DB objects from this same database and added some other objects specific to APP1 because it becomes bigger than APP0. And we do not need APP0 anymore as APP1 does all what we want, and more.
So, now, we are thinking about a way to find out which objects are used by APP1 in order to remove objects which are ONLY used by APP0.What is the best approach to discover all objects used by APP1 without having to open every single class and form?
Once we will have a complete list of these objects, it will be easy to use a program we bought which detects all dependencies for all SQL Objects specified directly from SQL and remove objects which do not return from any dependencies. Any ideas of how I could get this list without having to go through all our program that have many, many, many classes and forms?
Note : I know, in a perfect world, all calls to PSs and tables should be in a DAL but in the case of the application we're presently working on ... this is not our case! Yippy! (sarcastic yippy) ;)
Note 2 : This application is not using any ORM. So all queries are directly using SqlCommand. So any call to any DB objects are in string format.
I have a 5 tables in my database and i want to access all my tables togather at a time.e.g.I have a code for one table i.e. rs.Open "select * from Group_info", con, adOpenDynamic, adLockBatchOptimistic. instead of Group_info table i want to access 5 tables also as Login_table,User_info table,group_name table etc. How i do that
View 11 RepliesIs it possible to set a project default for VB.NET winforms projects so that the default Modifier for controls added to winforms is Private (not Friend)?I know there's a "modifiers" property in the properties window so I can set it for each individual control however I would like to change the project so from now on myself and other developers have to specifically decide to change from friend to private. (Which I would strongly discourage them from doing).I believe there is no way of doing this, but on another forum a while ago someone mentioned it would be possible with an add-in (but didn't name the add-in or where to get it).
View 1 RepliesI have a list of strings. How do I bind it to a listbox so that the listbox updates as the data of the list changes? I'm using vb.net.I've tried this so far. I've manage to display the data, but not change it:
Public Class Form1
Private mycountries As New List(Of String)
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[code]....
I've also tried this:
ListBox1.DataBindings.Add("items", mycountries, "Item")
But items is readonly, so it doesn't work.Also, if I want to bind the enabled property of a button to a boolean, how can I do that?I've tried this but I don't know what to add for the last parameter.
Dim b As Boolean = True
Button3.DataBindings.Add("Enabled", b, "")
SQL statements:
SQL = "SHOW TABLES;"
Try
conn.Open()
The remarked area works fine when I'm accessing a specific table. I've successfully inserted the products_model field into the combobox too. The datagridview does show the table names in the db using the SHOW TABLES sql statment, but I'm not understanding how to get this info into the combobox instead.
I have an ASP.NET page with a Wizard control containing several steps and about 80 form fields. The data is collected and inserted to a database from the code behind page. I need to set this form up so you can not only insert, but edit a record as well. So I want to databind the fields. I'd rather not use a FormView because then I would have to revise my existing code, since you can't access controls inside a FormView directly. Is there a way to databind the fields without using a FormView?
View 1 RepliesI have a button that i basically want to either show or hide it based on if a certain string has a value or not. I create the buttons in code so i was trying to used databindings with a converter but i can't seem to get the converter on the binding after the value changes. I'm not sure if I'm going after this correctly or not... Here is what i have for creating the button and the binding and the converter. "sFileLocation" is a string inside my class "QuestionsFile". This works for initialization but its just when the value of the string changes, this binding doesn't see the change and doesn't run the converter and all that for me...
Dim btn2 As New Button
Dim b2 As New Binding("sFileLocation")
b2.Mode = BindingMode.TwoWay
[code]....
The thing I don't understand too is that the binding works fine if i just binding the property to the Button.Content. So the property is updating correctly when it gets changed, and the buttons content changes accordingly.
I'm trying to do something with databinding between 2 controls...Here is a sample code (that doesnt work - and that is my wonder):
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'Me.TextboxPlus2.DataBindings.Add("Text", Me.TextboxPlus1, "Text")
[code]...
Is there a way to fill a checked list box with data from a sql table and then use the checked items as parameters or a stored procedure?
View 5 RepliesI have an ASP.NET page with a Wizard control containing several steps and about 80 form fields. The data is collected and inserted to a database from the code behind page. I need to set this form up so you can not only insert, but edit a record as well. So I want to databind the fields. I'd rather not use a FormView because then I would have to revise my existing code, since you can't access controls inside a FormView directly. Is there a way to databind the fields without using a FormView? I'm new at this by the way so sorry if the answer should be obvi
View 3 RepliesI want to databind my catagory table to a dropdown list but thecategories aren't going to be in order like:
categoryID Name---------------------1-----------apple2-----------wiper blades3-----------band aids4-----------pear5-----------raisons6-----------tiresHow would I be able to make the list look like:
[code].....
how to add sql statement in my code..here's my code for the form load..[code] want those textboxes to displayed only data for a particular person something like "Select * from Staffapplication where MID ='" & frmLeave.txtUser.Text & "'")how to add the sql statement in my code??
View 10 RepliesI would like to databind to a property that requires arguments.
I thought about defining custom columns and cells because the parameters that the property requires are available from the within the object bound to the row, but I'm having trouble materialising this idea.
As an additional problem, that I think leads on from this, I have also created a custom column and cell for the datagridview that takes the implementation of an interface during it's construction. I have added this column to the datagrid view programmatically (passing the Interface implementation to the column constructor). I've overridden the paint method which evaluates a property from the Interface implantation using arguments from the other rows in the column, but it doesn't seem to call the paint method at all. Even on DataGridView.Refresh(). Essentially I would like this column to also update, evaluate a property from the interface implentation using arguments from the underlying object bound to the row and print this number in the cell.
The reason for this second problem is so that I can implement the interface many different times and just at a column dynamically to display it's evaluation.
Is it better to perform data access operations on the page and then populate the properties of each usercontrol with the retrieved data. Is it better if each UC calls the business layer and pulls its own data independently without having to depend on the page.Existing Conditions:
1. Any information (Querystring, URL, etc) that the page would use for data access is also available to the individual UC's
2. Both solutions utilize caching.
My coworker insists that the first option is better since Data access only happens once on the page. The second option seems more logical to me since it will allow me to place the UC on another page without the need for any additional wiring on the page itself. The page and the UC are truly decoupled.
In this example the IsEnabled property of my button is bound to the selected rows "Local" property of the grid and it works just fine:
<Button DockPanel.Dock="Bottom" Width="100" Height="100" IsEnabled="{Binding ElementName=dataGridRestore , Path=SelectedItem.Local}"></Button>
<my:DataGrid x:Name="dataGridRestore"
ItemsSource="{Binding}"
[Code]...
I am trying to get some binding code working. Bascially I want to bind the IsEnabled property of an element of my grid's context menu with a value of the selected row in the grid.I have it working with this:
<my:DataGrid.ContextMenu>
<ContextMenu DataContext="{Binding PlacementTarget.SelectedItem, RelativeSource={RelativeSource Self}}">
[code].....
I have 2 tables with relation from parent table (customers) and child table (orders) and i have all inside typed dataset.
Now i want a field of customers by datarelation from field child table.
Inside child table i have IDCustomers and i want Customers.FirstName
I think so, inside databinding form designer, inside Text i write
dsMaster.Orders.CustomersOrders.FirstName