AngleSharp by Florian Rappl

<PackageReference Include="AngleSharp" Version="0.8.4.1" />

.NET API 1,229,312 bytes

 CssBorderImageSliceProperty

More information available at: https://developer.mozilla.org/en-US/docs/Web/CSS/border-image-slice or even better: http://dev.w3.org/csswg/css-backgrounds/#border-image-slice
using AngleSharp.Css; using AngleSharp.Css.Values; using AngleSharp.Extensions; using System; namespace AngleSharp.Dom.Css { internal sealed class CssBorderImageSliceProperty : CssProperty { internal static readonly IValueConverter<Tuple<Length, Length?, Length?, Length?, bool>> Converter = Converters.WithAny(Converters.BorderSliceConverter.Option(new Length(100, Length.Unit.Percent)), Converters.BorderSliceConverter.ToNullable().Option(null), Converters.BorderSliceConverter.ToNullable().Option(null), Converters.BorderSliceConverter.ToNullable().Option(null), Converters.Assign(Keywords.Fill, true).Option(false)); internal CssBorderImageSliceProperty(CssStyleDeclaration rule) : base(PropertyNames.BorderImageSlice, rule, PropertyFlags.None) { } protected override object GetDefault(IElement element) { return new Length(100, Length.Unit.Percent); } protected override object Compute(IElement element) { return Converter.Convert(base.Value); } protected override bool IsValid(CssValue value) { return Converter.Validate(value); } } }