combobox

问题 I have a combobox on my form (winforms). In the properties I have set the DisplayMember and the ValueMember. DisplayMember = Name and ValueMember = ID. The Combobox is populated with the following objects: public class MyObj { public string Name { get; set; } public int ID { get; set; } } The Name displays fine in the dropdown(so DisplayMember is working) however, when I do: mycombobox.SelectedValue it is ALWAYS null. Does anyone know if I've forgotten to do anything? 回答1: Have you set the

问题 I have a ComboBox that is part of a detail display related to a data grid containing rows from a database. No binding to the ComboBox exists, I am doing this manually. The ComboBox allows manual entry, as if it were a text field, while still providing a drop-down of choices. My issue is that if I have manually entered text in the field, and the drop-down is clicked, the ComboBox apparently wants to seek out a match. Also, it appears that the search is simple, so KG matches KG/Day . I must

问题 I'm basically trying to display different sets of textboxes on a userform depending on the value taken by a combobox. I have created a class module called CControlEvents in which I describe the events that should occur when I change the value of the combobox : Private WithEvents mclsCbx As MSForms.ComboBox Private WithEvents UnitmclsTbx As MSForms.TextBox Private WithEvents UnitmclsTbxLabel As MSForms.Label Private WithEvents SpecMinMoymclsTbxLabel As MSForms.Label Private WithEvents

问题 I want to show a ComboBox with OPTGROUP style header gruopings in Silverlight. Every website I find (including questions on SO) that sovle this link to an outdated link and, handily, show no code snippets for me to work from. E.g.: So how do I do this? 回答1: See my similar question: How to show group header for items in Silverlight combobox? I put dummy entries in collection source to indicate the group header and then modified DataTemplate to show the group headers in different way and normal

问题 I have a ComboBox in c# XAML and when nothing is selected and the PlaceHolderText is shown and I click on it to open, the normal behavior is to open it in the middle. I want the dropdown to open on top instead. Let's say I have a ComboBox and fill it with the number 1-100 , then I want it to display beginning from 1 . If there are seven items shown in the dropdown, then the numbers 1-7 should be visible. Normal behavior would be showing the numbers 47-53 . An old workaround would be using a

问题 I have a vaadin combobox that is filled with a containerdatasource setContainerDataSource(container); I now want to insert a static text somewhere in the list of results. For example: A Combobox that is filled with a container of and the first entry that pops up in the result list is some kind of header: Persons: Thomas S. Lucas B. Alex X. Can i achieve that by either manipulating the container or the combobox? I just tried to set the container source and add a String/Label via addItem() to

问题 I have a ComboBox, and that is how I fill the data in it: SectorCollection sectorCollection = sectorController.SearchAll(); comboSector.DataSource = null; comboSector.DataSource = sectorCollection; comboSector.DisplayMember = "titleSector"; comboSector.ValueMember = "idSector"; What I want is to set a pre data, like a text in the combobox without a value. Like "Select a Sector." So the user can knows what does he is selecting. 回答1: If you are using a WinForm combobox then you should code

问题 I am developing a Watermarked ComboBox by modifying the ComboBox ControlTemplate . Everything is fine when the ComboBox is not in an editable mode, but when I change the edit mode to True, the IsFocused property is never set to True. This is because in edit mode, the ComboBox is using a TextBox . This is an exact copy of this StackOverflow question: . There are no responses to that question. Please drop a line if you know how to solve this, or please point me to links that provide a Watermark

问题 I have this already populated ComboBox and all I want to do is to set it to a specific selectedItem knowing its value. I'm trying this, but nothing happens: comboPublisher.SelectedValue = livre.Editeur; Considering the fact that I already implemented Equals(..) method in my class Editeur, this way: public bool Equals(IEditeur editeur) { return (this.Nom == editeur.Nom); } This is how I populate my ComboBox: foreach (Business.IEditeur editeur in _livreManager.GetPublishers()) { comboPublisher

问题 I have a datagrid, with a combobox column <DataGridComboBoxColumn x:Name="DataGridComboBoxColumnBracketType" Width="70" Header="Tipo di staffa" SelectedValueBinding="{Binding type, UpdateSourceTrigger=PropertyChanged}"> </DataGridComboBoxColumn> I want an event that is fired only when the user changes the value into the combobox. How can I resolve this? 回答1: I found a solution to this on CodePlex. Here it is, with some modifications: <DataGridComboBoxColumn x:Name="Whatever">