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Read The Value Of A TextBox
f#

Hi all,

Normally I'd try to hack together some sample code to demonstrate this but I get the feeling I'm missing something pretty obvious.

I have a windows forms app that has several textboxes on it. These textboxes are on a panel. I modify the value in the text box and then read it via the PanelName.Controls.[x].Text property and it seems no matter what I do the value I get back is always the initial value.

I think I've got the syntax right because when I examine the value in the debugger, it shows up. It just never seems to register the change.

What am I missing? Or do I need to hack together some demo code to show this?

--

Onorio

.

Are you defining a value instead of a fn? E.g.:

let ZipCode = PanelName.Controls.[0].Text

should be:

let ZipCode() = PanelName.Controls.[0].Text

That would account for the value not changing.
Just an idea, if indeed your problem is F#-specific.

By on 3/24/2010 9:37 PM ()

Hi Another,

That changes the type of "ZipCode" from String to Unit. Doesn't look like it does the trick.

I'll just see if I can hack together some demonstration code to give a more definite question.

By on 3/25/2010 4:08 AM ()

The changes does not change the fn "from String to Unit" - the fn still returns a string - the () forces a fn which takes no arguments, and is the same as:

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let ZipCode = fun -> Panel.Controls.[0].Text

Such as:

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> let text() = "foo";;
val text : unit -> string

>printfn "%s" <| text() + text();;
foofoo

Anway, must be something else then...

By on 3/25/2010 7:31 AM ()

Thanks I've got it now although I'm not quite sure what it's about.

1.) You're right--have to add a () on the function def.

2.) Had to change the output type from Windows Application to Console Application. I need to look over the settings to figure out what this makes different.

I'm sharing this just in case anyone else runs into a similar issue.

By on 3/26/2010 9:01 PM ()

Yes--you're right; I didn't say it quite right. And you're right; without the (), it could simply be a string value and not a function returning a string.

I just need to hack together a small example--I have to believe I'm missing something pretty obvious because I don't believe I'm doing anything particularly out of the ordinary.

By on 3/25/2010 2:58 PM ()

Thanks, Another. That's a good suggestion. I'll give it a try. I am doing the former and I'll try the latter and see what I get.

By on 3/25/2010 2:58 AM ()

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