Xamarin - Bring string interpolation expression to XAML!

We all know how String.Format and string interpolation works in C# so I'm not going into details how Converter_StringFormat works in XAML.

To give a few example, here's how string formatting works in C#

C#

string name = "Jayson";
string day = "Morning";
var formattedText = string.Format("Hello {0}, Good {1}!", name, day);
// output
// Hello Jayson, Good Morning!

or the string interpolation which is introduced in C# version 6

string name = "Jayson";
string day = "Morning";
var formattedText = $"Hello {name}, Good {day}!";
// output
// Hello Jayson, Good Morning!

So coming from our second example, this is where our Convert_StringFomat based at for XAML

<Label>
 <Label.FormattedText>
  <FormattedString>
   <Span Text="{Binding ., Converter={StaticResource StringFormat}, ConverterParameter='• {Title}'}" FontAttributes="Bold" FontSize="15" />
   <Span Text="{Binding ., Converter={StaticResource StringFormat}, ConverterParameter='&#13;&#10;{Description} - Read more...&#10;by {Author} | {PubDate}'}" />
  </FormattedString>
 </Label.FormattedText>
</Label>

So to explain this a bit
"Binding ."
The "." is an object with properties "Title", "Description", "Author", and "PubDate"

This is how it looks like at run-time


So my 8 years issue is finally resolved. Starting from creating an app for Windows Phone 7 in year 2011

<TextBlock>
   <Run Text="{Binding Title}" />
   <LineBreak />
   <Run Text="{Binding Description}" />
</TextBlock>

to WPF, UWP, and up until Xamarin

<Label>
   <Label.FormattedText>
      <FormattedString>
         <Span Text="{Binding Title}" />
         <Span Text="&#10;" />
         <Span Text="{Binding Description}" />
      </FormattedString>
   </Label.FormattedText>
</Label>

and I can now simplify my XAML code

<Label Text="{Binding ., Converter={StaticResource StringFormat}, ConverterParamater'{Title}&#10;{Description}'}" />

One note though is, of course, this will not replace the way you format the font attributes. :)

So that's how it simply works. I hope this simple Converter can help you in someways

Here's a simple app I made that uses the Converter_StringFormat.

You can clone my code > Simple RSS Feed app in my github
https://github.com/Nullstr1ng/XamarinConverterStringFormat