Hi Eduardo,
> How can I develop a widget for WebAppBuilder to export a feature layer to Excel?
FYI, the Attribute Table widget has an option to export to CSV - which could then be imported into Excel.
Attribute Table widget—Web AppBuilder for ArcGIS | Documentation
Hope this helps,
Thank you so much, I have tried this functionality before, the problem is the CSV result is badly formatted, contents in one cell end up expanding to another cells if such content contains commas, leading to an unusable file. I have tried to fix it when reading the CSV in Excel, but without success.