js如何判断是否在iframe中及防止网页被别站用iframe嵌套

//方式一 if (self.frameElement && self.frameElement.tagName == "IFRAME") {   alert('在iframe中'); } //方式二 if (window.frames.length != parent.frames.length) {   alert('在iframe中'); } //方式三 if (self != top) {  alert('在iframe中'); } 

<script language="javascript"> <!-- if (top.location != location) { top.location.href = location.href; } //--> </script> //或 <script language="javascript"> if(self!=top){top.location.href=self.location.href;} </script> 

<iframe src="你的页面地址" name="tv" marginwidth="0" marginheight="0" scrolling="No" noResize frameborder="0" id="tv" framespacing="0" width="580" height="550" VSPACE=-145 HSPACE=-385></iframe> <script language="javascript"> var location=""; var navigate=""; frames[0].location.href=""; </script> 

<script language="javascript"> if(top != self){  location.href = "about:blank"; } </script> 

header("X-Frame-Options: deny"); header("X-XSS-Protection: 0");