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Variable for number of days

17-Nov-20 4:30

As far as I can see from your question, the values in the TempDataKey class represent the key of the TempData item. The message constants are defined in the Constants class, which is why I replaced that constant with the value from the resource file.

The TempData key will never be shown to the user.

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Member 1447460716-Nov-20 5:56

Member 14474607

16-Nov-20 5:56

Hello - I am constructing an URL to pass for API call.
It has a date value in it.

DateTime.Today.AddDays(0).ToString("yyyy-MM-dd")

Is there some way I can pass the (0) dynamically, reading from App.Config file?
I tried --

DateTime.Today.AddDays(ConfigurationManager.AppSettings["CompletedDays"].ToString("yyyy-MM-dd")

which errored out and did not work. Any way to do this?

Thanks!

Richard MacCutchan16-Nov-20 6:01

Richard MacCutchan

16-Nov-20 6:01

Member 14474607 wrote:
which errored out and did not work.

Sorry, there is no way we can guess what that means. Please edit your question and provide proper details of the problem.

Gerry Schmitz16-Nov-20 6:58

Gerry Schmitz

16-Nov-20 6:58

var revisedDateTime = DateTime.Now.AddDays( (int) ConfigurationManager.AppSettings["CompletedDays"] );

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Richard Deeming16-Nov-20 21:41

16-Nov-20 21:41

The AppSettings indexer returns a string. The code will compile, but will throw an InvalidCastException at runtime.

"These people looked deep within my soul and assigned me a number based on the order in which I joined."
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Gerry Schmitz17-Nov-20 4:57

Gerry Schmitz

17-Nov-20 4:57

50-50 chance. There are some value-object pair settings out there (UWP: ApplicationDataContainer)

It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food

Richard Deeming17-Nov-20 17:35

17-Nov-20 17:35

ConfigurationManager.AppSettings almost certainly refers to:
ConfigurationManager.AppSettings Property (System.Configuration) | Microsoft Docs[^]

That's a NameValueCollection[^], and the indexer[^] returns a string.

If there's a different ConfigurationManager class out there with the same name but different semantics, then it was poorly named. Smile | :)

"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer

Gerry Schmitz17-Nov-20 20:52

Gerry Schmitz

17-Nov-20 20:52

If you want to get picky, AppSettings is based on a NameObjectCollectionBase.

Not my fault it's protected. But I won't whine about it.

It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food

Richard Deeming16-Nov-20 21:43

16-Nov-20 21:43

int completedDays;
int.TryParse(ConfigurationManager.AppSettings["CompletedDays"], out completedDays);
return DateTime.Today.AddDays(completedDays).ToString("yyyy-MM-dd");

Int32.TryParse Method (System) | Microsoft Docs[^]

If the setting isn't a valid integer, completedDays will be set to 0. If you want to validate that the setting is valid, check the return value of TryParse.

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Changing the properties of multiple labels in some kind of loop?

pkfox18-Nov-20 21:11

pkfox

18-Nov-20 21:11

A much better way of doing things Richard - I often overlook TryParse and default to using one of the ConvertToxxx static methods

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Ron_UK16-Nov-20 4:55

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 4:55

Hello

My first post on here, would really appreciate some help.

I'm programming in C# (Visual Studio .NET Forms).

My form has 9 labels and i'm trying to change the visibility properties of all the labels in a loop instead of changing them individually.

For example :

label1.Visibility = true;
label2.Visibility = true;
label3.Visibility = true;
label4.Visibility = true;
label5.Visibility = true;
label6.Visibility = true;
label7.Visibility = true;
label8.Visibility = true;
label9.Visibility = true;

Instead of using the above laborious method, use some kind of for loop instead to select the labels number to make the changes, is this possible?

Many thanks
Ron Thumbs Up | :thumbsup:

Pete O'Hanlon16-Nov-20 5:00

Pete O'Hanlon

16-Nov-20 5:00

A common trick to solve this type of problem is to loop over all of the controls in your form. If you are able to cast the control to a Label, set the visibility then. Don't forget to take into account that the code you write to loop over the controls has to take into account that some of the controls on your form might have children and there may be labels in those children.

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Re: Changing the properties of multiple labels in some kind of loop?

Ron_UK16-Nov-20 5:17

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 5:17

Hi Pete

Thanks for your input.
That's what i'm trying to do, loop over all the controls but it's making the loop that i'm having difficulty with.

I see someone has just left me some example code so will check that out now, perhaps it's what i need.

Cheers
Ron

OriginalGriff16-Nov-20 5:06

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 5:06

There are several ways: the messiest is to scan the Forms Controls collection:

foreach (Control c in Controls)
    {
    if (c is Label lab)
        {
        lab.Visible = true;
        }
    }

It's messy for two reasons:
1) If any of the labels are within a container (e.g. a Panel) then you need to recurse through all container Controls collection as well.
2) If there are any labels you didn't want to hide, you have to "tag" them somehow to prevent you affecting them.

A neater solution is to construct an array or List of the labels you want to work with, and use that instead of the Form Controls collection. It's a little work to set up, but it's more specific and easier to code.

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Ralf Meier16-Nov-20 5:16

Ralf Meier

16-Nov-20 5:16

but to de-messy it :
he could check the Label-Name if it corresponds to those Labels he wants to work with.

Re: Changing the properties of multiple labels in some kind of loop?

OriginalGriff16-Nov-20 5:27

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 5:27

That's nasty as well, particularly once he realizes that sticking to VS default names for everything is a really bad idea ... Laugh | :laugh:

Ron_UK16-Nov-20 5:36

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 5:36

LOL! the default names seem fine to me, no problems yet and been using it for years.

Every so often you need to do something unusual and this is one of those cases.
I'm soon to work on a program with 256 labels to display register values from a chip so need to create another loop program to run through and update all the values in both hex & binary.

If i change the label names to say result1, result2, result3.
Could i use an alternative loop method to select the label name seeing they have digits at the end?

OriginalGriff16-Nov-20 5:48

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 5:48

Do yourself a favour, and stop using Visual Studio default names for everything - you may remember that "TextBox8" is the mobile number today, but when you have to modify it in three weeks time, will you then? Use descriptive names - "tbMobileNo" for example - and your code becomes easier to read, more self documenting, easier to maintain - and surprisingly quicker to code because Intellisense can get to to "tbMobile" in three keystrokes, where "TextBox8" takes thinking about and 8 keystrokes...

plan for maintenance: it will happen, and your memory of what is what will fade. Using descriptive names means that you can pick it back up faster in a few months time!

And 256 labels? Oh dear.
Use a DataTable instead, and set that as the DataSource for a table-based control (DataGridView) instead. It's a lot tidier, and much, much easier to work with (and layout neatly with scroll bars as required, and so forth)
It's also a lot easier on the user as well - you can provide search facilities very easily so they can find which register they are interested in much more quickly!

Ron_UK16-Nov-20 5:58

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 5:58

Hi Griff

Sound advice, thank you.

I'm being lazy Griff, I normally program Microcontrolles and always choose descriptive names for registers so i should really be more descriptive with Visual Studio names.

Yer i know, 256 labels, lol, i'm a glutton for punishment that's for sure.
I've only just changed them to text boxes as they look pretty smart all laid out.

I'll check the Data Table you mentioned, never had to use one before so will take a look in a moment.
VS has so many smart tools, i've only every used 25% of them over the years.

Thanks again for your help.
Ron Smile | :)

Ron_UK16-Nov-20 5:19

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 5:19

Hi Griff

Ahhhhhh, that rings a bell now, thanks for the example.
Brain needed a gentle nudge, been a while since i did it.

Thanks for replying so quickly and for the advice.

Cheers
Ron

OriginalGriff16-Nov-20 5:27

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 5:27

You're welcome!

Ron_UK16-Nov-20 8:39

Re: Changing the properties of multiple labels in some kind of loop?

16-Nov-20 8:39

Hi Griff

The code worked a treat, thank you.
I just adjusted it to work with my text boxes instead of labels and hey presto.

Hopefully this info will help another poor soul in the future.

Many thanks
Ron

OriginalGriff16-Nov-20 9:29