Thanks for your inquiry. Aspose.Words does not provide API for spid and spt. Aspose.Words supports the Shape.AlternativeText which get or set the alternative text (description) of shape.
In your case, I suggest you please use Shape.AlternativeText property. Hope this helps you. See the attached image for the detail of alternative text (description) of shape.
Document doc = new Document(MyDir + "in.docx");
Shape shape =
(Shape)doc.getChild(NodeType.SHAPE, 0, true);
doc.save(MyDir + “Out.docx”);
Can we use Shape.setShapeAttr (int key,Object value) API for this? If so, what is the key value to be passed?
This method is used for internal use of Aspose.Words. This is not public method. Please do not use this method.