源代码:
<!DOCTYPE html> <html> <body> <iframe id="myframe" src="demo_iframe.htm" marginheight="50" marginwidth="50"> <p>Your browser does not support iframes.</p> </iframe> <br><br> <p>The value of the marginwidth attribute is: <script> document.write(document.getElementById("myframe").marginWidth); </script> <p> </body> </html>
运行结果：