We Keep Coding

DevExpress RepositoryItemComboBox enter text without showing caret

I am using RepositoryItemComboBox inside a DevExpress.XtraGrid.GridControl. I have very specific requirements for the behavior of the RepositoryItemComboBox. One of these is as follows:
On receiving focus, the combo box should not show caret. It should not highlight (select) the current text.
On keyboard input, the combo box should not show caret, but should update the edit value.
Is it possible to achieve this behavior with RepositoryItemComboBox?

You're probably looking for TextEditStyle = TextEditStyle.DisableTextEditor?

How to Invoke Selecting from a Combobox

I know how to use
Invokemember("Click")
to simulate clicking in web browser. But I cant find the c# code for simulating the selection and then clicking an option from a combo box in a specific URL.
The selection can be done by:
webBrowser1.Document.GetElementById("id").SetAttribute("value","option");
but this only changes the text of the combo box in the web page. It does not update the page based on the selected option in the combo box. And again
Invokemember("Click")
does not do anything in this case.
Thanks in advance.

Combobox with checkbox in winforms

I am trying to look for a simple way to design a winform with a combobox that has checkbox values in it to select multiple values.
But there are no free samples I could find.
If anybody has a good link for a sample which does not require a license.
Please let me know.
I am not looking for controls like telerik and infragistics.

Maybe this example can help you.
CheckBox ComboBox Extending the ComboBox Class and Its Items

It sounds like what you really want is a checked listbox control or maybe even just a listbox. These controls do multi-select in a way that is more standard for Windows.
If you really need a combo box with checkboxes in it, here's an article on code project I used once.

My suggestion, if space is an issue as #rmc00 has eluded to, place a button at the end of a readonly Textbox with perhaps an elipse (...) or down arrow (same as combobox) as the text of the button and when clicked or MouseDown make visible and position a CheckBoxList or open a popup dialog with a CheckBoxList this way you can either prepopulate at design time or pass a DataTable as a parameter/property to your control/form so it is databound at runtime. You can always place your control or write code to position the control/form exactly below your TextBox in the MouseDown/Click event. On check change update your textbox with a comma separated list (or go fancy and say if more than 3 items the text box can have the list stored in the Tag and the TextBox Text can have the count of items checked). Finally on LostFocus hide the Control (or Form), and further if you want to get fancy make the exception to not hide when the ActiveControl is the Button that way you can toggle the visibility of consecutive button presses.

How to edit values in a c# listbox

This is more of a UI Design approach on how to let the user edit values in a list box.
I am interested in the Usability issue.
First approach is having a textBox near the list.
When user selects an element in the list, the text goes to the textbox.
My second though is having an input box coming up (a modal) and edit the value there.
Another option is to use a list view and let the user edit inline. This might be tricky if the user doesn't know this is editable (not all user do)
What would you prefer? Any suggestions on a different approach?

I have used data binding to bind text boxes and numeric controls to a listbox. As the list box selection is changed then the relevant data appears in the controls.
Another way is a property grid linked to the current selected item in the list box. That works well for users who may be relatively savvy for the property grid.

As far as I think I would go for your second approach. I would like an edit button. When I select any item in the list box, edit button should be enabled. When I click edit a small modal dialog saying ok or cancel and in textbox displaying the current value which I can edit.

I think a list view looks a lot cleaner, and people are getting more used to this kind of thing as more web pages use client-side script, Ajax, etc.
I don't like the idea of a modal popup - very clunky.

I did this recently using a hidden text box that I would show positioned over the list box item populated with the selected item text when the user double clicked or pressed F2. When the user pressed enter or the text box lost focus, the text box was hidden and the list box item text was replaced with the edit box text. If the user pressed escape, the text box was hidden and the list item text remained unchanged (i.e cancel).

Getting handle of Autocomplete dropdown box of textbox in winforms

I wanted to adjust the width of the Autocomplete dropdown box of a textbox. I dont want to adjust the width of that textbox, but only Autocomplete dropdown. I know that there is no way I can increase the width of the Autocomplete dropdown by using properties provided with textbox.
Hence I wanted to know whether there is any way to get the handle of that Autocomplete box and then increase the width of that drop downlist without changing the textbox width?
If this is not possible then I would like to create my custom textbox with autocomplete, in this case how to use the existing autocomplete functionality provided by microsoft? Is there any way to do it. Are there any libraries available for this?

I don't think you can use Microsoft's implementation of autocomplete, which does not have an option to adjust dropdown width.
Create a background thread to not get into the way of typing, and hook up the text change event of a combobox box or a textbox to update the candidate list (assuming autosuggest mode since you mention a dropdown). You can probably add/remove the combobox items on the fly if you have a combobox. But for dropdown list and textbox items you need a popup window
It is easy to get a popup to show, but you need to not use a fixed position so it won't go off the screen when the textbox is close to the edge of the screen. And the focus logic is a little bit complex. you need to keep focus on the textbox unless the user press the arrow keys to make a selection.
so
when focus is on textbox:
arrow keys move the focus to the popup
other keys goes to the textbox, if not handled by the dialog itself, except for the delete key when mouse is over the popup.
when focus is on popup:
arrow keys move the focus to the sibling candidate item or the textbox
other keys goes to the textbox, if not handled by the dialog itself, except for the delete key
mouse clicks:
dismiss the popup outside of the popup or the popup.
update the value of textbox if a candidate item in the popup is clicked on
It takes a lot of effort to get the focus/threading right. If you can afford some form space, you can just add a fixed width listbox to the form instead, like Visual Studio help viewer's index pane.

After going through lot of blog posts and different articles, I came to a consensus that it is next to impossible to get a solution to my problem in the way I wanted. So I've decided either to come up with a custom solution or as Sheng Jiang said I need to implement my own autocomplete object.
I've come up with a solution which fits my requirement by increasing the width of the textbox as per the largest string in the autocomplete string list while I'm adding the autocomplete custom source. As I said I cant increase the width of the text box because of the size constraint on the form, so I decided to keep this textbox in a panel and increase the size of the textbox inside that. Panel will not grow with the textbox so that solved my problem.
I know this is not perfect solution but it fits my requirement.