ArcGIS Pro 2.6 API Reference Guide
ArcGIS.Desktop.Core Namespace (ArcGIS.Desktop.Core)
Inheritance Hierarchy
The ArcGIS.Desktop.Core namespace contains classes used to create and manage ArcGIS Pro projects. After creating or opening a project, developers can retrieve and work with the items it contains such as maps, layouts tasks, styles, and other resources. Developers can determine if changes to the current project are waiting to be saved, and set properties such as its home folder.
Classes
 ClassDescription
Class The ArcGISPortal class is part of the Pro Portal API which provides a way to build applications that work with content from ArcGIS Online or an ArcGIS Portal. ArcGIS Portal is software technology from Esri that customers can deploy either on premise or in the cloud. ArcGIS Online is Esri's Software as a Service offering that represents GIS as a Service and is implemented using the same technology as ArcGIS Portal. The Portal API allows application developers to work with users, groups and content hosted within ArcGIS Online or within an ArcGIS Portal.
Class Manages the collection of portals currently defined for Pro. Portals can be added to and removed from the ArcGISPortalManager. The list of portals is shown on the Portals backstage tab.
Class The BrowseProjectFilter class is used to control the behavior of the open and save dialogs by controlling what is visible and what can be browsed into
Class ClipboardItem is a light-weight item representation used by Pro for copy/paste
Class IContentsProviders will return an instance of this class for their "contents". Contents are shown in the Contents Dock pane when the IContentsProvider is activated.
ClassRepresents the core module, which provides access to the current project
Class Provides the settings used to create a new project
Class Base class for deriving custom items. Custom items are shown in the Catalog View and Pane
ClassBase class for deriving custom project items. Custom project items are custom items that can be persisted within a project aprx.
Class A custom project item container contains custom project items of a specific type that have been added to a project.
Class Provides a class for perfroming HTTP communication with a resource identified by a Uniform Resource Identifier (URI).
Class Represents the collection of Request Headers as defined in RFC 2616.
Class Provides a class representing HTTP response message.
Class Represents the managed exception base class for custom ArcGIS.Desktop.Core exceptions
Class Represents an item that is available to be used in the current project
Class Provides a base class for ItemCategory classes defined in DAML
Class 
ClassCreates items that can be added or imported to the project
Class Thrown when an invalid portal is provided as the active portal.
Class Encapsulates the ArcGISPro application.
Class The Pro application
Class Represents an ArcGIS Pro project
Class Basic information associated with a ProjectItem
ClassContains the status of the Portal SignIn. This includes the success of failure of the SignIn and the current token (if succesfull)
Class Interaction logic for StartPageNewProjectContent.xaml StartPageNewProjectContent
Class Interaction logic for StartPageOpenProjectCotent.xaml StartPageOpenProjectCotent
Class Represents a class to provide parameters to the Upload method on EsriHttpClient class.
Class Represents a primary window within the application that persists its view state with the project. This is an abstract class.
Interfaces
 InterfaceDescription
Interface Implement this interface on the View Model associated with your Contents control to override the default Contents caption or make your control read-only.
Interface Support clipboard operations from your contents control
Interface 
Interface Panes must implement this interface to show their Contents in the Contents dock pane (eg a custom TOC)
Interface Defines factory methods for item creation
Interface Implemented by items that support metadata
InterfaceProvides basic interface for all project items
Interface Implemented by items that support import
Interface Implemented on catalog view panes. Indicates whether the details view is being shown and the parent item of any items that are selected.
Interface Use this interface to select items and retrieve the current selection
Interface 
Enumerations
 EnumerationDescription
Enumeration Flags used by the BrowseProjectFilter to represent groups of item types
Enumeration Specifies the exceptions that may occur when attempting to use a project or project template, a map or layout file, or a package
EnumerationSpecifies the type of item that will be created using ItemFactory.Create, then added or imported to the project
Enumeration Enumeration of options for filtering sensitive content out of an item’s metadata. The item’s metadata content is filtered before it is exported to a standard metadata format. The amount of content that is filtered out of the item’s metadata is determined by the option selected.
Enumeration Enumeration of options for importing metadata to and exporting metadata from an item. Used to identify the XML format of a metadata document that will be imported, or the XML format of the metadata document that will be created on export. An appropriate transformation will take place between the ArcGIS metadata XML format and the indicated XML format. On import, the resulting ArcGIS metadata is saved to the item. Remarks: On import, if the selected option identifies an XML format that doesn’t match the XML format of the source metadata document the wrong transformation will be performed. The resulting content that is formatted as ArcGIS metadata can be missing some or all of the original content.
Enumeration Enumeration of options for saving an item’s ArcGIS metadata to an HTML file. The item’s metadata content can be exported to HTML format for display or use outside the ArcGIS platform. The XSLT stylesheet used to perform this conversion is indicated by the option selected.
Enumeration Enumeration of options for saving an item’s metadata to an ArcGIS metadata format XML file. The item’s ArcGIS metadata content can be saved to an XML document where the content continues to be stored in the ArcGIS metadata XML format. The amount of content that is filtered out of the item’s metadata depends on the option selected.
Enumeration Enumeration of options for upgrading an item’s metadata to the ArcGIS metadata format. This option is provided to update metadata that was created with ArcGIS Desktop 8.x or 9.x..
Enumeration Gets and sets the project system template type that will be used to create the new project
See Also

Reference

ArcGIS.Desktop.Core Assembly