.NET Tutorials, Forums, Interview Questions And Answers
Welcome :Guest
Sign In
Win Surprise Gifts!!!

Post New Web Links

Not successful with SelectedIndex = -1 for Combobox

Posted By:      Posted Date: September 16, 2010    Points: 0   Category :Windows Application
My Windows form has three comboboxes. Combobox2 references a child table of combobox1, and Combobox3 references a child table of combobox2. I want the three comboboxes not to show a selectedItem until the user selects a value.  I have this set when the Form is first shown:         private void Form1_Shown(Object sender, EventArgs e)         {             this.comboBox1.SelectedIndex = -1;             MessageBox.Show("You are in the Form.Shown event.");         }          private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)         {             if (isClosing == false)             {                 try                 {                     String cb1Value = comboBox1.SelectedValue.ToString();     

View Complete Post

More Related Resource Links

System.ArgumentOutOfRangeException 'ComboBox' has a SelectedIndex which is invalid because it does



I think I have a complicated one here.

Synopsis: I have a AJAX enabled ASP.Net application, the purpose of which is to allow users to ad hoc drill an engineering database.  The application UI is divided into three sections, Filtering, Column Selection, and Results. The filtering section (implemented as a user web control) uses a PlaceHolder control, to which I allow addition and removal of individual Filter user controls.

All of that works well. The Filter user control essentially consists of three ComboBox controls with SqlDataSources bound to each of those ComboBoxes, and a TextBox to enter in a value. The first ComboBox, once a value is selected in its list, passes the SelectedValue to the SqlDataSource of the next ComboBox, which uses that value as a Select Parameter so the DataSource can fill out the ListItems of the next ComboBox. So simply, the results of the previous one cascade to the next.

Again, all this worked well. But one of the requirements was to allow storage of these queries the customer comes up with, allowing them to reload the query at a later time to run again.

I implemented that by writing a simple set of container classes, Filter, Column, and Query, where Query has public arrays of Filters and Columns. I serialize that simple Query object, then store it as XML in my database. To reload i

How to display related tables in one crystal report and how to link this report with combobox?


Hi! I want to display a crystal report in my vb.net application. Suppose I have tables named student details, student marks, student address, etc... Now if I want to display all these details (fields of all tables) in one crystal report (with page breaks if necessary) then how will I achieve it. I will be providing a combo box in my application that contains list of student names. How can I link this combo box with the cystal report to dynamically display report for different student on selected index change of combo box? Help me friends. An example would be appreciable.

C++ at Work: Addin a Combobox Cancel Feature


This month Paul DiLascia codes some Microsoft Office-style dialog box features.

Paul DiLascia

MSDN Magazine August 2006

ActiveX and Visual Basic: Enhance the Display of Long Text Strings in a Combobox or Listbox


The combobox and listbox controls in Visual Basic have no built-in support for displaying text strings that are too long to fit in the visible area of either control. This article describes several techniques to improve the readability of long strings in each control. The first technique uses tooltips to display a combobox or listbox item. The other techniques, which use various Windows APIs, include adding a horizontal scrollbar for a listbox and determining the necessary width of the longest string given the font attributes of the text. The required steps are described for both comboboxes and listboxes.

John Calvert

MSDN Magazine December 2000

Binding value to combobox or dropdown


How can we bind a value to a combobox or dropdown? What is the property for binding a value? 


Weird "string;#" in combobox


Ok, while I am digging and digging myself into the world that's called Sharepoint I come to the next challenge.


I have two lists Projects List and Project Issues. They both have an id field (which is not the ID field of the record) and a title. I created two calculated fields for both of the tables which combines the title and the number for displaying in other pages.



Projects List:

ProjectID: 2008-001

Project Name: First Project in 2008

Display Name (which is the calculated field): 2008-001 First Project in 2008


The calculated field formula is: =[ProjectID]&" "&[Project Name]

The field returns a string.


I also have a Worksheet list where my workers have to fill in their working hours. In this list I have two lookup fields. O

Combobox and Enter key


I have added a combobox to my page. Listview is updated based on selection from combobox. It is working great except it does not fire when Enter is pressed. User has to click on option from dropdown or has to press tab key to have Listview to populate. I want the user to be able type use arrow key to select option and then press the enter key for event to fire.

Using .net 3.5 and c#


ComboBox text/value selection?


When we select a value from combobox list, we can get it by combobox.selectedvalue.text, however when we enter a new value in combobox, we can get it by combobox.text when submitting a form.  During submission, how will we handle this situation? Either there is a single way of getting value in both situations or we'll have to tackle both situations separately?

Please help me tackling this situation. Thanks

How to bind to DisplayMemberPath in a customercontrol that derived from ComboBox?

Hello, All: I need a customer control which derives from ComboBox. In its resource file I have the style:   <Style TargetType="{x:Type local:MyComboBox}">             <Setter Property="SnapsToDevicePixels" Value="True"></Setter>             <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>             <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>             <Setter Property="ScrollViewer.CanContentScroll" Value="True"/>         <Setter Property="ItemTemplate">                 <Setter.Value>                     <HierarchicalDataTemplate>                     <CheckBox Content="{Binding Path=DisplayMemberPath,Mode=TwoWay,RelativeSource={RelativeSource

combobox with first row blank

Hi  I have combobox whith data biding to another combo box but i have a problem,when I open UI windows already initially  i see value inside combo box but i need in at the start to display blank combo box only after choosing value i need to display it/ thank

WPF ComboBox Loaded Event - Handling Globally

Hello, I am having trouble hooking up to a WPF ComboBox Loaded event when trying to do it globally with EventManager.RegisterClassHandler in the parent control rather than with XAML right on the control.  Here is the code for the ComboBox control: <DataTemplate x:Key="MyUIEditor"> <ComboBox Width='Auto' x:Name="Combo" ItemsSource="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:MyControlWPG}}, Path=MyCollection}" SelectedValue="{Binding Value}" DisplayMemberPath="Name" SelectedValuePath="FullName" Background="Transparent" /> </DataTemplate>   Here is the code for the global event handler:   public partial class MyControlWPG : UserControl public MyControlWPG() { InitializeComponent(); EventManager.RegisterClassHandler(typeof(ComboBox), ComboBox.LoadedEvent, new RoutedEventHandler(Combo_Loaded)); } The event handler gets hit when I declare Loaded = "Combo_Loaded" in the XAML right on the ComboBox control but not when I use the global handler.  Any ideas as to why it doesn't get hit when doing it this way?

Combobox SelectionChanged: Prevent firing for every keystroke?

Is it possible for this event to fire only when the user clicks an item from combobox with the mouse or when they hit enter on it like the old 2.0 combobox worked? I have tried messing aroudn with the new selectionchanged event but I cannot figure it out. I looked on the forums here for help but only found someone returning the even to fire only when items they type are in the combobox. Thanks all help appreciated.GINtech Systems Owner

how to get selected value from combobox?

i have combobox which populated with data from sql db now when user select value i want to get selected value in combobox in this code i get the place of the value in sql table but not value himself can anyone help me??   private   void button1_Click(object sender, RoutedEventArgs e) {     int selectedIndex = comboBox9.SelectedIndex;   Object selectedItem = comboBox9.SelectedItem;   MessageBox.Show("Selected Item Text: " + selectedItem.ToString() + "\n" +   "Index: " + selectedIndex.ToString()); } i get showbox  "  slected item text system.data.dataRowView"

SQL Server 2005 Express Edition Service Pack 3 (KB955706) update is successful but repeats installin

  Microsoft SQL Server 2005 Express Edition Service Pack 3 (KB955706) (update 1 of 1) This update seems to be stuck in a loop of installing, each time it successfull installs acccording to automatic updates. Then says it requires installing again straight away. This has been happening for 10 days now. I have tried a manual update from the website rather than automatic updates, no change. Any ideas why? Have posted in Windows update which is where I think the problem lies but they have suggested I post here also.

AjaxToolkit:ComboBox not working in ModalPopupExtender

Hello,I have two nested modal popup. The ComboBox does not work as expected as you can see frome this screenshot. As you can see it misses:The list is not visible even if I think that is in the background. In fact the "SuggestAppend" works perfectly.The ComboBox arrow button is not visible. On zooming the green circle you can see that it shrinked to a size of 4x4 pixelsAdditional info: jquery is used for tabs & datePicker (in the first popup) and Buttons (always)EDIT: Forgot to include  the server side code. Here it is:<ajaxToolkit:ComboBox ID="dataPhoneType2" runat="server" DataSourceID="phoneTypeDS" DataValueField="PhoneTypeId" DataTextField="Description" AutoPostBack="False" DropDownStyle="DropDownList" AutoCompleteMode="SuggestAppend" RenderMode="Inline" CaseSensitive="False"></ajaxToolkit:ComboBox>Is this a bug?Regards

Combobox in DataGridView

Hi, How do I setup a selected value for a combobox column in datagridview? Unlike a regular combobox I can't use: SelectedValue = 1; I'll give an example :Let's say I have a datagrid which is consisted of two datasets tables: one table which contains 300 entries for different types of cars, and a combobox column which contains a list of 10 car makers (that's the second table). The car maker's code is the primary key in the combobox column's value member and the foreign key in the first table. How do I load the datagrid so that t the combobox will display the correct car maker for every car entry (300 in total)? here's my current code: private void SetupDataGridView() { this.Controls.Add(carsGrid); DataGridViewComboBoxColumn comboGrid = new DataGridViewComboBoxColumn(); carsGrid.DataSource = dsCars.Tables[1]; carsGrid.DisplayMember = "CarMakerName"; carsGrid.ValueMember = "CarMakerID"; carsGrid.DataSource = dsCars.Tables[0]; carsGrid.Columns.Add(comboGrid); } Thanks, Udi

Sorting a ListBox or ComboBox on a Converted Value

Is it possible to apply a Converter to the SortDescription of a CollectionViewSource?  My ViewModel contains a List<> of a class that contains an enum and a Boolean.  My XAML displays a multi-select ListBox, showing the localized names of the enum values using a Converter in the View, and binds each ListBoxItem's IsSelected to the Boolean in the members of the bound List<>.  That's working.  Now I want to sort the ListBox items by those localized enum names, without reordering the List<> in the ViewModel.  Is this possible, and if so, how can it be done?
ASP.NetWindows Application  .NET Framework  C#  VB.Net  ADO.Net  
Sql Server  SharePoint  Silverlight  Others  All   

Hall of Fame    Twitter   Terms of Service    Privacy Policy    Contact Us    Archives   Tell A Friend