Full page refresh, iframe page not refreshed? How to solve it

The whole page refreshes, the IFRAME page does not refresh???
When you refresh the entire page, the IFRAME also refreshes, returning to the first blank page. I want to refresh this page, the IFRAME display loading page information, to solve the prawn!!!
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Specify the SRC for the IFRAME
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The Beginning Plus

Header ("Expires:   Mon,   1997   05:00:00   GMT");   
Header ("Cache-control:   no-cache,   must-revalidate");   
Header ("Pragma:   no-cache");

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Refresh is the reload process, which of course shows the default.
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You can first write the URL of the iframe into a cookie, refresh and then determine whether the cookie exists, there is a URL to read the cookie as an iframe src, or use the default src.

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