PeachDrawing
PeachDrawing.RasterCanvas
RasterCanvas.BeginVariableText() Method
Begins the /Tx marked-content sequence ISO 32000-1 §12.7.3.3 requires around the
value drawn into an interactive form field’s appearance stream, and
EndVariableText() closes it. It is what tells a PDF reader which part of the
generated appearance to replace when the user edits the field - without it the reader
draws the new value over the generated one instead of in place of it. Deliberately a pair
of its own rather than reusing EndMarkedContent(): these two must sit outside
any text object, while that one has a caller that is legitimately inside one.
public override void BeginVariableText();