<iframe src="html/bai.jsp" frameBorder=0 id=middle name=middle scrolling="yes" style="HEIGHT: 400; VISIBILITY: inherit; WIDTH: 100%; Z-INDEX: 1"> </iframe>
$("#middle").contents().find("tbody tr");
<iframe src="html/bai.jsp" frameBorder=0 id=middle name=middle scrolling="yes" style="HEIGHT: 400; VISIBILITY: inherit; WIDTH: 100%; Z-INDEX: 1"> </iframe>
$("#middle").contents().find("tbody tr");
原文：https://www.cnblogs.com/xdcr/p/8718540.html