Revert chages in EntityCollection on click of cancel

I have a wpf window wherein grid is bound to entityCollection. herein I add/dele开发者_开发问答te a record to grid and then click cancel button. How can I revert the chages made to the entitycollection.

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Doesn't EF require you to call SavChanges() before anything is saved in to the database? You don't need to add a cancel button but rather a save button.

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if your objects states were changed you can't do anything without reloading collection from server using with Overwrite option.

In better case you may use Memento pattern.