Office integration in D365

In D365 Microsoft Excel can change and quickly analyze data. Dynamics includes an Excel Data Connector app that interacts with Excel workbooks and Dynamics OData services that are created for publicly exposed data entities. The Excel Data Connector app enables Excel to become a seamless part of the Dynamics user experience also it has static feature to export of grid data, directly to an excel spreadsheet. This is useful for quick analysis of data.

The Excel Data Connector app is built by using the Apps for Office framework. It runs in a task pane that contains all app-related actions and information. Office applications are web applications that run inside an embedded Internet Explorer browser window.

There are three primary scenarios for Excel Data Connector:

Workbook Designer 

In Workbook Designer, the user can select an entity and some fields. The entity and its fields are bound to the workbook. Any data changes can be published back, provided that all the key fields have been included.

Custom Generated Export

Developers can use the Export application programming interface (API) to add a custom export to any page. These custom exports make it easier to edit the data in Excel.

Template Export

Developers can use the Export API to add a template export to any page. These template exports are like custom-generated reports, but they use a predefined template. These template exports also make it easier to edit the data in Excel.

For detail understanding you can refer Microsoft Documentation Office integration