Ability to Assign Custom Properties or Unique IDs to Individual Cells

Summary I'd like to request support for assigning custom metadata — such as unique IDs or arbitrary key-value pairs — directly to individual cells in Excel using the Office.js API. Why This Matt...

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James1981

Copper Contributor

Sep 05, 2025

Could you not use EntityCellValue interface? https://learn.microsoft.com/en-us/javascript/api/excel/excel.entitycellvalue?view=excel-js-preview

https://learn.microsoft.com/en-us/office/dev/add-ins/excel/excel-data-types-entity-card

chetankotwal

Iron Contributor

Sep 08, 2025

Hi James1981 ,

Thanks for the suggestion. But I think entitycellvalue interface primarily used for entity cards and linked data types. You can’t arbitrarily assign it to a cell unless the cell is bound to an entity source. Also it doesn’t guarantee persistence or movement with the cell during structural changes.