How does the smarty template assign values to the <iframe> embedded part of html?

How does the smarty template assign values to the & lt; iframe & gt; embedded part of html? For example, set the php variable $ example
$ Smarty-> assign ('example ', $ example );
$ Smarty-> display('index.html ');

$Examplecan be passed to the index.html page and displayed, but How can I obtain this variable in the right sidebar of an embedded webpage? &lt;Br/&gt; Please contact smarty for advice &lt;p&gt; &lt;/p&gt; &lt;br/&gt; reply to the discussion (solution) &lt;p class = "sougouAnswer"&gt; besides writing to iframe using js, iframe content comes from an independent url &lt;/p&gt; &lt;p class = "sougouAnswer"&gt; You are inside the nested iframe &lt;{$ example}&gt; &lt;br/&gt; &lt;/p&gt; &lt;p class = "sougouAnswer"&gt; &lt;iframe&gt; is another ?? Face, in iframe? Face? You can. &lt;/P&gt; &lt;p class = "sougouAnswer"&gt; &lt;p class = "yy"&gt; You are in the nested iframe &lt;{$ example}&gt; &lt;/p&gt; &lt;br/&gt; can I write it directly? After the page is opened, &lt;{$ example}&gt; &lt;/p&gt; &lt;p class = "sougouAnswer"&gt; &lt;p class = "yy"&gt; &lt;iframe&gt; is another?? Face, in iframe? Face? You can. &lt;/P&gt; &lt;br/&gt; However, after the page is opened, the &lt;{$ example}&gt; such code cannot output the expected value &lt;/p&gt; &lt;p class = "sougouAnswer "&gt; &lt;p class =" yy "&gt; besides using js to write to iframe, iframe content comes from an independent url &lt;/p&gt; &lt;br/&gt; So what should I do? &lt;/P&gt; &lt;p class = "sougouAnswer"&gt; How do you write an independent page? &lt;/P&gt; &lt;p class = "sougouAnswer"&gt; in my opinion, let alone Smarty and talk about your business needs first. &lt;Br/&gt; Why is this variable obtained? When will this variable be obtained? &lt;Br/&gt; variables can be passed through the embedded &lt;iframe&gt; url parameters.