Update Version History Programmatically

In my webpart I need to populate the data from the sharepoint lists and libraries.

I have an option to change the data in the UI and that should reflect the same in the lists/libraries when i click on 开发者_如何学运维save button.

Problem is even if I am not changing the data and click on save the new versions are adding in my version history with out any changes..

This brings lot of problems in the audit. I need solution/code that it should update the version history only if the item(list row) is changed when we click on save button.

You need to put this logic in the code itself. Before overwriting the list item, compare the list item with the previous version and if its same, do not overwrite.