As has been said previously, you cannot get the contents of an <iframe>
if its source is not from the same origin.
This also applies to most other ways of getting external content, such as using ajax to load source code from another page. ie: $('#div').load('http://www.google.com');
To load external content, the content must comply with the same origin policy.
This means that the content must be on the same protocol and host.
Wikipedia Article Linked Above:
httpː//www.example.com/dir/page2.html --> Success Same protocol and host
httpː//www.example.com/dir2/other.html --> Success Same protocol and host
httpː//username:password@www.example.com/dir2/other.html --> Success Same protocol and host
httpː//www.example.com:81/dir/other.html --> Failure Same protocol and host but different port
https://www.example.com/dir/other.html --> Failure Different protocol
http://en.example.com/dir/other.html --> Failure Different host
http://example.com/dir/other.html --> Failure Different host (exact match required)
http://v2.www.example.com/dir/other.html --> Failure Different host (exact match required)
Simply put, it must be on the same website. So while example.com/hello.html
can load content from example.com/goodbye.html
, it could not load content from google.com/content.html
Also, it must be on the same domain. Sub domains are considered to VOID the same domain policy so while weebly.com/hello.html
can load content from weebly.com/goodbye.html
, it could not load content from user1.weebly.com/content.html
There are of course workarounds, as usual, but that's another story all together. Actually, this is quite relevant to the question. So here is a wonderful questions 'thread' on all the ways to bypass it.