Setting Combobox to first item

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Hi,

I would like to programactically set a combobox back to the first item. Since the data in the combobox is dynamic, I can't just simply set the text to a value.

I've tried mycombobox.SelectedIndex = 0; - The code executes but it still displaying the previously selected item.

Any help would be greatly appreciated.

Thank you,

[UPDATE]
Hi,
I'm writing in WinForms and this event is attached at a SelectedIndexChanged for a different combination box. I thought it should work and I was doing it correctly, I'm just not sure why it's not. Maybe I need a call to Application.DoEvents(); ?
[/UPDATE]

Posted 7-Jan-11 3:57am

gmhanna

Updated 7-Jan-11 5:30am

Nuri Ismail

v3

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Nuri Ismail 7-Jan-11 11:33am

I've deleted your fake answer and updated your question with the information from your answer.
Next time if you want to clarify something about your question please just update your original question and/or post a comment to answer(s).

3 solutions

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fjdiewornncalwe · Answer 1 · 2011-01-07T04:03:00

Solution 2

Are you writing WinForms/WPF/Web???
In any case. Make sure your code for .SelectedIndex = 0 is actually firing where you expect it to and that it isn't being overriden by another assignment somewhere else because the statement will work if it is used in the right place.

--Edit:
Based on the article Sandeep posted, you will need to do a .SelectedIndex = -1 followed immediately by a .SelectedIndex = 0 to guarantee that each and every time this block runs the result is the first item selected.

Posted 7-Jan-11 4:03am

fjdiewornncalwe

Updated 8-Jan-11 6:51am

v2

Comments

Sandeep Mewara 7-Jan-11 11:31am

Comment from OP:
Hi,

I'm writing in WinForms and this event is attached at a SelectedIndexChanged for a different combination box. I thought it should work and I was doing it correctly, I'm just not sure why it's not. Maybe I need a call to Application.DoEvents(); ?

fjdiewornncalwe 7-Jan-11 12:48pm

You should never need to call Application.DoEvents(). The architecture of the form should be written so that you don't need to. (Personal opinion)
My suggestion would be to put a breakpoint on that line and see if it gets hit and set correctly. If it does get hit, examine all the objects carefully and you'll likely find the root of your problem.

Sandeep Mewara 7-Jan-11 13:07pm

Article link I shared - it exactly points out the issue/bug that you pointed out about clearing.

Sandeep Mewara 8-Jan-11 12:49pm

:) Ok.
5!

Sandeep Mewara · Answer 2 · 2011-01-07T05:34:00

Solution 4

As much as I remmeber, it should be
mycombobox.SelectedIndex = -1;

Have a look at this article[^].

Posted 7-Jan-11 5:34am

Sandeep Mewara

Comments

thatraja 7-Jan-11 11:37am

You right, it's -1. 5!

fjdiewornncalwe 7-Jan-11 12:46pm

Wrong... -1 removes all selected items. 0 is the index of the first item so you have to set to 0 to select the first item.

Sandeep Mewara 7-Jan-11 13:06pm

Article link I shared - it exactly points out this issue/bug.

fjdiewornncalwe 8-Jan-11 12:47pm

The article shows exactly why = -1 is incorrect. I the user wants the first item to get selected every time he executes this, then = 0 is the correct way to do it. The OP specifically isn't trying to clear the box, but select the first item. I think you just missed that little detail in his question. Your answer would be correct in all cases if you suggest that he select = -1 and follow that immediately with = 0. If he does that he can guarantee that the first item is selected. Cheers...

Member 10800885 6-May-17 2:30am

Marcus... you are right :)

velmahesh · Answer 3 · 2011-01-07T20:36:00

Solution 5

so, you initialise the value is -1.

Posted 7-Jan-11 20:36pm

velmahesh

Comments

fjdiewornncalwe 8-Jan-11 12:48pm

Are you adding anything to a previous answer? Please read those before posting something like this.