ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Desktop.Layouts Namespace / SpatialMapSeries Class / PageNumberField Property
Example Version

PageNumberField Property
Gets or sets the index layer's page number field.
Syntax
public string PageNumberField {get; set;}

Property Value

Type: String
Remarks
Optional. If not set, automatic page numbering is applied. You can offset the starting value using the StartingPageNumber property. The page number field can be string defined to include page numbers like roman numerals, for example.
Example
Modify an existing map series
//Modify the currently active map series and changes its sort field and page number field.

//Perform on the worker thread
await QueuedTask.Run(() =>
{
  SpatialMapSeries SMS = layout.MapSeries as SpatialMapSeries; //cast as spatial map series for additional members
  SMS.SortField = "State_Name";
  SMS.SortAscending = true;
  SMS.PageNumberField = "PageNum";

  //Overwrite the current map series with these new settings
  layout.SetMapSeries(SMS); 
});
Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3 or higher.
See Also