Copyright © 2014 by tutorialspoint
The contents( ) method finds all the child nodes inside the matched elements (including text nodes), or the content document, if the element is an iframe.
Here is the simple syntax to use this method:
Here is the description of all the parameters used by this method:
Consider you have a blank html file index-blank.htm which we would use in an iframe.
Try the following example which shows how you can access the objects in an iframe from a parent window. This operation has become possible just because of contents() method.
var $content = $("iframe").contents();
$content.find("body").append("I'm in an iframe!");
<iframe src="/jquery/index-blank.htm" width="300" height="100">
To understand it in better way you can Try it yourself.