Is it possible to embed the Google Docs editor so that it reads a file, which is then uploaded to a server (not google docs server) and you can edit it and save back to same file?
I don't think this is currently possible with Google Docs.
Yes it is:
< iframe height="300" src="https://docs.google.com/spreadsheet/ccc?key=0AgRoqAerkV0-dE1TS1BKVGk0cUFSNi1HZG10dFNEU0E&usp=sharing&embedded=true" width="75%" >
It's possible to edit an existing document. You must only put the following.
To save file in another server, you must capture event on click in the frame and if yoy want to create new, you must create the file on gmail server then download on to your server.
来源：https://stackoverflow.com/questions/8226222/embed-google-docs-editor-into-webpage