PHP variable not rendering in IFrame

This seems like a silly thing, but I have been banging my head against the wall so I thought I'd ask here

I have this code:

<?php
    echo '<iframe style="width:<?php echo $width; ?>px;height:100%"  src="hike_widget.php?hike_id='.$hike_id.'&height='.$height.'&width='.$width.'" >
    </iframe>';
?>

And if I do a view source on that, it shows this:

<iframe style="width:<?php echo $width; ?>px;height:100%" src="hike_widget.php?hike_id=108&height=450&width=450" > 
</iframe>

Which is weird because on the same line, the same PHP variable renders correctly, and right next to it in the style snippet, it just renders as text. Any idea 开发者_运维百科why this is happening? Thanks!

---

This line doesn't make sense:

echo '<iframe style="width:<?php echo $width; ?>px;height:100%"  src="hike_widget.php?hike_id='.$hike_id.'&height='.$height.'&width='.$width.'" >

PHP doesn't work that way; you can't nest <?php tags.

Instead, you should be closing your string and passing $width to the echo statement. The line should look like this:

<?php
echo '<iframe style="width:', $width, 'px;height:100%" src="hike_widget.php?hike_id=', $hike_id, '&height=', $height, '&width=', $width, '" >';
?>

---

echo '<iframe style="width:' . $width . 'px;height:100%" src="hike_widget.php?hike_id='.$hike_id.'&height='.$height.'&width='.$width.'" ></iframe>';