I created a grid with recordtype, I have 10 fields in my recordType but on grid am showing only five fields, when i click export to excel button it exports on five fields data, but i want all of the field should be exported.
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In that case, you should consider adding a dropdown that controls what fields should be visible, and then if the user wants to add more fields in the export, they'll be able to do it.
You can refer to this article to see how you can add such a dropdown - appianspace.com/.../