Utf8String.cs

using System.IO;
using System.Text;
using System.Threading.Tasks;
using System.Xml;
using Waher.Script;
 
namespace TAG.Simulator.ObjectModel.Values.BinaryElements
{
    public class Utf8String : SimulationNode, IBinaryElement
    {
        private StringAttribute value;
 
        public Utf8String(ISimulationNode Parent, Model Model)
            : base(Parent, Model)
        {
        }
 
        public override string LocalName => nameof(Utf8String);
 
        public override ISimulationNode Create(ISimulationNode Parent, Model Model)
        {
            return new Utf8String(Parent, Model);
        }
 
        public override Task FromXml(XmlElement Definition)
        {
            this.value = new StringAttribute(Definition.InnerText);
            return Task.CompletedTask;
        }
 
        public async Task Append(MemoryStream Output, Variables Variables)
        {
            string s = await this.value.GetValueAsync(Variables);
            byte[] Bin = Encoding.UTF8.GetBytes(s);
            int c = Bin.Length;
            int i = c;
            byte b;
 
            do
            {
                b = (byte)(i & 127);
                i >>= 7;
                if (i != 0)
                    b |= 128;
 
                Output.WriteByte(b);
            }
            while (i != 0);
 
            Output.Write(Bin, 0, c);
        }
    }
}