Develop Reference

displaying the square root of "X" in label

I have written a simple calculator program in C# which can also calculate the square root of any number.
So, I was just wondering if you could display said number in a label. Or rather display it like you would when calculating in real maths where the number is under the square root
(https://images-na.ssl-images-amazon.com/images/I/51Vo0t5w5YL.jpg).
Is that even a possibility? For those curious:
//Root
if (CW3.Checked) //Square Root Box checked
{
if (Z3N.Checked) //Negativ Number Box checked
{
MessageBox.Show("You can't get the square root of negative numbers.");
}
else
{
Zahl3 = Math.Sqrt(Zahl3);
}
}

It sounds like it's just a small project, so perhaps you could use something like this:
<Grid HorizontalAlignment="Center">
<Label Content="13.2" HorizontalAlignment="Left" VerticalAlignment="Center"/>
<Label Content="√" HorizontalAlignment="Left" VerticalAlignment="Center" FontSize="18" Margin="-11,-2,0,0"/>
<Grid Height="1" Background="Black" Margin="3,-13,3,0"/>
</Grid>
Just copy it all and insert it instead of the label you have. And change the number - bind the content or edit from code behind or whatever you do. There might be some fidgeting with the margins, but that is all part of the fun. TextBlocks might be the way to go instead of labels though.

Why WPF XAML front end looks diffrent on other machines?

I wrote a WPF C# application and every element of front end is adjusted in margins, for example:
<TabItem x:Name="ClipboardItem" FontSize="15" FontFamily="Century Gothic" Height="60" Header="
Multi Clipboard" Background="#2a2a29" Foreground="#e7e8ea" Margin="-4,-7,-57,8">
On my computer, everything looks good and just how i wanted. Weird thing is about other PCs. For example on other PC2 element let's call it A looks diffrent and run over but on other PC3 element A looks exactly like on my PC but other element B looks totally diffrent. To the point, on other PCs some elements are just like they should be, but some elements are not. It's window application with rigidly set height and length. Could you tell me how to fix that?

First of all. computers can come in many different resolutions and aspect ratios. so if you want to fit them all. use GridView or a ViewBox (there's more but these are good for starters). and it's not recommended to use margins for most elements unless it's small and in a corner then again don't use that.
use something suitable instead of HorizontalAlignment="Stretch"
<GridView HorizontalAlignment="Stretch" >
<TabItem x:Name="ClipboardItem" FontSize="15" FontFamily="Century Gothic"
Height="60" Header=" Multi Clipboard" Background="#2a2a29"
Foreground="#e7e8ea">
</GridView>
Learn about Grid Views before you try this code https://learn.microsoft.com/en-us/dotnet/desktop/wpf/controls/gridview-overview?view=netframeworkdesktop-4.8
if you want to maintain the aspect ratio Use View Box:
https://stackoverflow.com/a/290229/10518289
One other thing to keep in mind that all computers you test on must run the same version of .Net Framwork or the latest.

How to bind an automatically-set parameter in WPF with MVVM

So here's the situation:
I have a label (custom control derviative of it, if it matters), and I need to get its width and height with MVVM. However, if I set either of the parameters to {Binding XXX}, they are no long Auto and thus when I change the font in runtime their size doesn't update.
I read about using ActualWidth/Height, which sounds like just what I need besides the fact that it's not a dependence parameter, thus it seemss like I'd need to break MVVM for it.
Are there any better solutions?
EDIT
Well, the element in XAML looks nothing special. Just a million of bindings.
<local:DraggableLabel
Content="123"
Margin="{Binding Label2Position, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
HorizontalAlignment="Left"
VerticalAlignment="Top"
FontFamily="{Binding Label2Font.Family}"
FontSize="{Binding Label2Font.Size}"
FontWeight="{Binding Label2Font.Weight}"
FontStyle="{Binding Label2Font.Style}"
Foreground="{Binding Path=Label2Color,
UpdateSourceTrigger=PropertyChanged,
Converter={StaticResource ColorToBrushConverter}
}"/>
The default is,
Width="Auto"
which doesn't have to be written explicits, but can (changes nothing). It makes it resize when the font changes. If I set it to
Width="Binding {Label1Width}"
The binding works fine, but I no longer get the auto-adjustment.

Okay, so I found a workaround.
Since I had create a custom control, I was able to create a new DependencyProperty called RealWidth, then I added a OnSizeChanged event that updates it with the value of ActualWidth that you CAN get from inside the element every time the size of the element changes.

Formatted Textboxes for UWP

I was wondering if anybody had any recommendations on how I could format a textbox for time inputs(hh:mm:ss) as well as Coordinates in Degrees,Minutes, Seconds (dd°mm'ss"). I am well aware that you can set the format of a string by the String.Format() method.... this does give me the desired layout in the textbox, but I want a control that has the appropriate symbols locked in and will autotab over those symbols as the user gives their inputs.
I have been searching for a way to do this in C#/UWP for a while with no luck, if anybody has any suggestions or could point me in the right direction it would be greatly appreciated.

The UWP Community Toolkit has some very good controls which are easy to integrate and one of them is the TextBox Mask control which is ideal for your scenario.
You can also try out the TextBoxRegex control which is not quiet what you want but is indeed something you should check out before proceeding.
Please reach out in case you are having difficulty in integrating the control for your specific requirement.
Optionally, you can download the sample app for the UWP toolkit to know about all the available controls /Tools. (UWP Community Toolkit Sample App)
EDIT 1:
As you might have noticed, the default behaviour for tab is that it sets the focus to the next control. Thus, having a single control will not be ideal since on press of tab, your textbox would lose focus and you would need to update the text and set the focus back to your textbox.
A relatively simpler way would be the following:
<StackPanel Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center" BorderThickness="1">
<StackPanel.BorderBrush>
<SolidColorBrush Color="{ThemeResource SystemBaseHighColor}"/>
</StackPanel.BorderBrush>
<TextBox x:Name="hour" MaxLength="2" BorderBrush="{x:Null}" VerticalAlignment="Center" HorizontalAlignment="Center" LostFocus="hour_LostFocus"></TextBox>
<TextBlock Text=":" HorizontalAlignment="Center" VerticalAlignment="Center"></TextBlock>
<TextBox x:Name="minute" MaxLength="2" BorderBrush="{x:Null}" HorizontalAlignment="Center" VerticalAlignment="Center" LostFocus="minute_LostFocus"></TextBox>
<TextBlock Text=":" HorizontalAlignment="Center" VerticalAlignment="Center"></TextBlock>
<TextBox x:Name="second" MaxLength="2" BorderBrush="{x:Null}" HorizontalAlignment="Center" VerticalAlignment="Center" LostFocus="second_LostFocus"></TextBox>
</StackPanel>
This is basically your custom build control/usercontrol. So that when user tabs out it moves to the next textbox inside the stackpanel and so on.
In your hour_LostFocus event you can validate the textbox's current value and append 0 and do other validations .
private void hour_LostFocus(object sender, RoutedEventArgs e)
{
string val = (sender as TextBox).Text;
Regex regex = new Regex(#"^([0[0-9]|1[0-9]|2[0-3])$");
Match match = regex.Match(val);
if (!match.Success)
{
//append 0 and other validations
}
}
The same applies for minute and seconds .. just that the regex would be different in these cases.

WPF formatting labels with StringFormat

I have a WPF application. I have some labels and some datagrids which are bound to some public properties. Some of these properties are numerical values.
In the datagrids I have been using the line below to ensure the values only display two decimal places, which works. However when I use the same line below for my label it appears to have no effect on the display as the number shows to about 9 decimal places. I don't understand why it works for the datagrid but not the label?
StringFormat={}{0:0.##}
<Label Grid.Row="3" Grid.Column="1"
Content="{Binding Obs.Tstat, StringFormat={}{0:0.#}}"
HorizontalAlignment="Center" Foreground="{StaticResource brushLinFont}"
FontSize="13" FontWeight="Bold"/>
Updated code
<Label Grid.Row="3" Grid.Column="1"
Content="{Binding Obs.Tstat}" ContentStringFormat="{}{0:0.#}}"
HorizontalAlignment="Center" Foreground="{StaticResource brushLinFont}"
FontSize="13" FontWeight="Bold"/>

For label you need to use ContentStringFormat:
<Label Content="{Binding Obs.Tstat}" ContentStringFormat="{}{0:0.##}"/>
Reason:
Label's Content property is of type object and StringFormat is used only when binding property is of type String.
If you try your code with TextBlock's Text property it will work fine with StringFormat because Text property is of type string.

Just a quick addition I'd like to post along these lines in case anyone else runs in to it... My application uses localization since it has multi-country support, but we also support user's system settings. We noticed ContentStringFormat defaults to your UI culture.
That caused an issue in one of our forms where the user's machine-specific decimal places they had configured in windows settings were not respected when you specified the ContentStringFormat.
Since the ContentPresenter simply takes the string format without the converter culture you could normally specify in the binding , this means that a format of say: 0:N will only return two decimal places if English is my current UI culture, even though I have 5 decimals specified on my windows settings.
In our case we applied some binding overrides to work around this, but mainly just wanted to add this extra bit of info in case anyone else runs in to it ;)