Horizontal/Vertical Line
Control Line
Draw a Line Manually

Note: no trendline support for 3D charts and Box charts.

Horizontal/Vertical Line
For information on Horizontal/Vertical Line, please refer to Horizontal/Vertical Line in 2D Line API.

Control Line
For information on Control Line, please refer to Control Line in 2D Line API.

Draw a Line Manually
For information on Draw a Line Manually, please refer to Draw a Line Manually in 2D Line API.

Please refer to QbChart, IDataPointSet, IHorzVertLine, IControlLine, IAnnotationSet, & IAnnotation in EspressChart APIDocs for additional information.