C# Discussion Boards - CodeProject

Re: Exception

sangramkp9-Jul-07 3:21

sangramkp

9-Jul-07 3:21

But i am working on a windows forms application

Re: Exception

Luc Pattyn9-Jul-07 2:43

Luc Pattyn

9-Jul-07 2:43

Hi,

a ListBox item can have any type you choose, all the items in a ListBox
dont even have to have the same type.

Foreach insists that each item in the collection has the indicated type,
otherwise an Exception will be trown.
If the types differ and you want to process only one of the types, say you
only want to process the strings, then do the following:

foreach (object item in collection) {
    string str=item as string;
    if (str!=null) {
        .. handle the str
    }
}

Luc Pattyn

try { [Search CP Articles] [Search CP Forums] [Forum Guidelines] [My Articles] }
catch { [Google] }

Re: Exception

sangramkp9-Jul-07 3:10

sangramkp

9-Jul-07 3:10

Hi pattyn

While i am trying to use
foreach(ListItem item in listbox1.Items)
{

}

It shows an error:
Error 1 The type or namespace name 'ListItem' could not be found (are you missing a using directive or an assembly reference?)

Re: Exception

Luc Pattyn9-Jul-07 3:19

Luc Pattyn

9-Jul-07 3:19

So ?
I never told you to use the ListItem class, did I ?

Luc Pattyn

try { [Search CP Articles] [Search CP Forums] [Forum Guidelines] [My Articles] }
catch { [Google] }

Re: Exception

ruanr9-Jul-07 3:32

ruanr

9-Jul-07 3:32

I really like your sig XD

Re: Exception

Luc Pattyn9-Jul-07 3:47

Luc Pattyn

9-Jul-07 3:47

Thanks.

I devised it to encourage people to search CodeProject before asking
simple questions for which the answers are readily available...

Smile | :)

Luc Pattyn

try { [Search CP Articles] [Search CP Forums] [Forum Guidelines] [My Articles] }
catch { [Google] }

Re: Exception

Not Active9-Jul-07 3:52

Not Active

9-Jul-07 3:52

Except it hasn't worked in this case Poke tongue | ;-P

only two letters away from being an asset

Re: Exception

Luc Pattyn9-Jul-07 3:59

Luc Pattyn

9-Jul-07 3:59

Yeah, what would we do without simple questions ?
We would have to investigate the hard ones !?

Smile | :)

Luc Pattyn

try { [Search CP Articles] [Search CP Forums] [Forum Guidelines] [My Articles] }
catch { [Google] }

For and next loop... problem

smguc9-Jul-07 2:28

smguc

9-Jul-07 2:28

Hi,

I am trying to insert selected items from a listbox into a label, the listbox is fillby a database query, the problem is all I get is this System.Data.DataRowView it works fine when I dont use a database query and just text in the listbox.

Cant anyone help on a solution for this??

Dim i As Integer<br />
       For i = 0 To ListBoxUpgrade.Items.Count - 1<br />
           If ListBoxUpgrade.Items(i) Then<br />
               LabelSum.Text = LabelSum.Text & Space(6) & ListBoxUpgrade.SelectedItem(i) & vbCrLf<br />
            End If<br />
        Next i

Thanks in advance!
Stefan.

"All answers have a question? All code has an end."

Re: For and next loop... problem

valerian.precop9-Jul-07 2:46

valerian.precop

9-Jul-07 2:46

I don't use VB very much but from what I know in C# if you use something like
ListBox1.SelectedItem[i] it would not work.
ListBox1.SelectedItem[i] returns a ListItem this one has a Text and a Value property.
I think you should use something like ListBoxUpgrade.SelectedItem(i).Text

Hope it helps...

Just call me Valy... Smile | :)

Re: For and next loop... problem

Corinna John9-Jul-07 2:49

Corinna John

9-Jul-07 2:49

You must select a column index for the DataRowView. Try this:

<br />
for(int i=0; i<ListBoxUpgrade.Items.Count-1; i++) {<br />
 if(ListBoxUpgrade.Items[i].IsSelected) {<br />
  LabelSum.Text += "      " + ((DataRowView)ListBoxUpgrade.SelectedItem[i])[yourIndex] + "\r\n";<br />
 }<br />
}<br />

____________________________________
There is no proof for this sentence.

Re: For and next loop... problem

V.9-Jul-07 3:24

9-Jul-07 3:24

you would be better of posting this in the VB forum instead of the C# forum... Smile | :)

Re: For and next loop... problem

smguc9-Jul-07 12:28

smguc

9-Jul-07 12:28

Thanks,

Sorry I thought I had!

My bad.

"All answers have a question? All code has an end."

Re: For and next loop... problem

V.9-Jul-07 20:07

9-Jul-07 20:07

no worries, if you browse long enough trhough CP you can tell the difference between people making a mistake and people just being lazy Smile | :)

.

There is no bad in making a mistake, it makes us human Wink | ;-)

V.

Stop smoking so you can: Enjoy longer the money you save.
Moviereview Archive

Do something while the mouse button is down

Dana Tov9-Jul-07 2:21

Dana Tov

9-Jul-07 2:21

Hi,
In windows application - I want the user to press a button
and while the button is pressed I will do something...
I tryed the mouse down event but it only doing it once
and I want to do the same function as long as the button is pressed (or the mouse button is down)

Thanks

dana Tov

Re: Do something while the mouse button is down

Colin Angus Mackay9-Jul-07 2:30

Colin Angus Mackay

9-Jul-07 2:30

On the mouse down event start a new thread that does the work. On the mouse up event signal the other thread to stop working.

Upcoming events:
* Glasgow: Mock Objects, SQL Server CLR Integration, Reporting Services, db4o, Dependency Injection with Spring ...

"I wouldn't say boo to a goose. I'm not a coward, I just realise that it would be largely pointless."

Ready to Give up - Your help will be much appreciated.

My website

Re: Do something while the mouse button is down

Dana Tov9-Jul-07 2:44

Dana Tov

9-Jul-07 2:44

Thanks!!
Is there a way to do it in a single thread?

dana Tov

Re: Do something while the mouse button is down

Luc Pattyn9-Jul-07 2:48

Luc Pattyn

9-Jul-07 2:48

Hi,

a keyboard key has autorepeat, so it will generate multiple KeyDown and KeyPressed
events when you hold the key down. A mouse button does not.

If you need a repeat for the mouse button (or a faster repeat for a keyboard key)
you can use a Forms.Timer that runs all the time, and checks whether the ccndition
is satisfied (either key is down or mouse button is down).

For "key is down", set a variable lastKey to the key that is down in KeyDown,
and set it to Keys.None in KeyUp; for "mouse is down" use Control.MouseButtons
(there also is Control.ModifierKeys for CTRL/ALT/SHIFT).

Smile | :)

Luc Pattyn

try { [Search CP Articles] [Search CP Forums] [Forum Guidelines] [My Articles] }
catch { [Google] }

Re: Do something while the mouse button is down

sam#9-Jul-07 3:14

sam#

9-Jul-07 3:14

Mouse down is a single thread event -TRUE
But you can use multi threading in it.
start a thread on mouse down and
stop it on mouse up

Re: Do something while the mouse button is down

Martin#9-Jul-07 3:26

Martin#

9-Jul-07 3:26

sam# wrote:
start a thread on mouse down and
stop it on mouse up

Dejavue![^]

Re: Do something while the mouse button is down

sam#9-Jul-07 3:33

sam#

9-Jul-07 3:33

i am sorry!! i didn't see that Mr. Martin.
but it seems you are quite good in peeping other's reply

Re: Do something while the mouse button is down

Martin#9-Jul-07 3:39

Martin#

9-Jul-07 3:39

sam# wrote:
i didn't see that

I assumed that.
I forgot to mark it as "Joke"

sam# wrote:
Mr. Martin

Come on!

sam# wrote:
but it seems you are quite good in peeping other's reply

Really???

Re: Do something while the mouse button is down

Luc Pattyn9-Jul-07 4:00

Luc Pattyn

9-Jul-07 4:00

Luc Pattyn

try { [Search CP Articles] [Search CP Forums] [Forum Guidelines] [My Articles] }
catch { [Google] }

Re: Do something while the mouse button is down

Hesham Yassin9-Jul-07 22:42

Hesham Yassin

9-Jul-07 22:42

you can do it using two events:
1. when mouse down
2. when mouse get off the button range

in step #1, you know that the mouse is down. in step #2 you know that the mouse left the button, then you can stop the thread you started in the first event! Smile | :)

High Definition Video Starting Point

paul90389-Jul-07 2:14

paul9038

9-Jul-07 2:14

Wondering if anyone can point me in the right direction, as a starting point, in building a frame accurate High Definition Video player i.e. must be able to control the HDV at the frame level. Have been spending time looking into various SDK's like WMV HD, DirectShow and DirextX with no clear concensus on the correct direction. Any pointers would be apprciated. Thanks

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