Steps to share XAMPP project on 
           Dropbox:

    1)   You should have Dropbox installed.
    2)   You should have installed XAMPP.
    3)   Copy your XAMPP project put it in
           Dropbox and share the project folder
           using Dropbox web portal.
    4)   Enter the path in the textbox 
           as given "C:/xampp"
           not as "C:\xampp"
    5)   Once you click Done you will get a 
           command prompt window,
           Enter Dropbox path till /htdocs
           ex: C:/users/name/Dropbox/Sharing/htdocs  

Your XAMPP files will be synced into dropbox,