this projects bases on the Nemmet project of deanebarker at https://github.com/deanebarker/Nemmet
this library is ported from the .NET 4.5.2 (the old project from deanebarker) to a .NET Standard 2.0 library.
you can use this library in all .NET projects like .NET Core, .NET Legacy, Xamarin, etc.

install the lib from nuget: https://www.nuget.org/packages/de.lkraemer.nemmet

var code = "#my-panel.panel>.heading{Title}+.content{Content}+.footer";

// To get a nested List<NemmetTag>
// NemmetTag has a recursive ToHtml() method
var tags = NemmetTag.Parse(code);

// To get the HTML as a string (which just concats the results of ToHtml())
var html = NemmetParser.GetHtml(code)

Result:

<div id="my-panel" class="panel">
  <div class="heading">
    Title
  </div>
  <div class="content">
    Content
  </div>
  <div class="footer"></div>
</div>

Read the Emmet syntax guide for the basics. Here the subset that Nemmet supports.

• Simple elements: div
• Nested elements: parent>child
• Sibling elements: div1+div2
• The "climb up" operator: parent1>child^parent2
• IDs: div#id
• Classes: div.class1.class2
• Attributes: div[key=value]
• Multiple attributes: div[key1=value1 key2=value2]
• Content div{Some text}
• Default tag naming (though, the defaults need more definition)

• Repeating elements and auto-numbering (why would you need this at runtime?)
• Parentheticals/grouping (though, this is likely not far off -- I have a theory for it)
• Style abbreviations (not hard, but low on the priority list)

Nemmet is an homage to Emmet (Nemmet = "Not Emmet"...get it?), the HTML expansion language.

I wanted something in (1) a single file, (2) pure C#, and (3) source that I could debug through. It will never be as full-featured as Emmet. I'm hoping for maybe 75% on a good day.