Fluid Values

Fluid only deals in FluidValue objects. Everything you inject into a scope will be converted into a FluidValue object. Indeed, the properties dictionary on Scope only holds FluidValue objects.

There’s a method on TemplateContext that takes a string and a FluidValue:

context.SetValue("name", StringValue.Create("Deane"));

(I know, I know – we haven’t been explicitly creating FluidValue objects in prior examples. We’ll explain this when we get to Value Convertors.)

Here are the built-in Fluid values:

Most of the provided classes have a private field for _value which holds whatever the original value was.

Fluid Values provide a common interface. Some highlights:

So long as you provide this functionality, you can create your own values. For example, if we wanted to value that wrapped a string and appended “ is awesome” to it when it output, we could do this:

public class AwesomeValue : FluidValue
  private string _value;
  public AwesomeValue(string value)
    _value = value;

  public override void WriteTo(TextWriter writer, TextEncoder encoder, CultureInfo cultureInfo) => writer.Write(ToStringValue());

  public override string ToStringValue() => $"{_value} is awesome";

  // We don't really care about any of this, but FluidValue is
  // abstract, so we have to override it all
  public override FluidValues Type => FluidValues.String;
  public override bool Equals(FluidValue other) => false;
  public override bool ToBooleanValue() => false;
  public override decimal ToNumberValue() => 0;
  public override object ToObjectValue() => ToStringValue();

When we set this value in the context –

context.SetValue("name", new AwesomeValue("Deane"));

– it will output this wherever it appears:

Deane is awesome

We pushed an AwesomeValue into the Context, and it was placed in the Scope. When a template finds it, the WriteTo method will create the desired output.

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