Can you help me on how to disable the exportation of vector layers especially in AutoCAD DXF, DBF File and ESRI Shapefile?
The only way would be to use WMS to view data so that no data is directly loaded to QGIS, and use wfs with featureid if required to edit.
You can actually disable the Save As vector functionality altogether in QGIS but this will only work provided that QGIS is running on Windows. It will be useful in an enterprise environment where the user doesn't have access to the Registry.
In QGIS go to Configuration > Customization > Tick the checkbox Enable customization.
Edit the system registry to set the following key to false:
You can still right-click and select Save As but the dialogue box doesn't have the OK button.
Source: Prevent export to shapefile from postgis table in QGIS. I tested it on QGIS 2.x