fileformat-slides-gists

// Create an instance of new presentation
Presentation presentation = Presentation.Create($"{documentDirectory}/{filename}");
// Create an instance of TextShape
TextShape shape = new TextShape();
// Set text of the TextShape
shape.Text = "FileFormat.Slides Text Shape Example";             
// Create Slide
Slide slide = new Slide();
// Add text shapes.
slide.AddTextShapes(shape);               

fileformat-slides-gists

 Presentation presentation = Presentation.Open($"{documentDirectory}/{filename}");
 // Get Slides
 var slides = presentation.GetSlides();
 var slide = slides[1];
 // Get Images from slide
 List<Image> images = slide.Images;
 // Choose desired image
 var image = slide.Images[0];
 // Set xAxis
 image.X = xAxis;

fileformat-slides-gists

// Create instance of presentation
Presentation presentation = Presentation.Create($"{documentDirectory}/{filename}");
// Create slide
Slide slide = new Slide();
// Set background color of slide because default background color is black.
slide.BackgroundColor = Colors.Silver;             
// Adding slides
presentation.AppendSlide(slide); 
// Save presentation
presentation.Save();