Need to check the value in a cell before closing

Dear Friends
I have a worksheet where I need to make sure some range is filled with data before saving.
I will keep a button for save and close and when I click the button it should check the range (for eg A1: B10) and make sure that the cells are not empty and it has some content in it. If any cell within that range is empty, I should get a msg that cell is empty.
could you please help me to code. I am stuck.
Thanks