js跨域有关问题之跨域iframe自适应大小

js跨域问题之跨域iframe自适应大小

前几天做公司和开心网合作项目的时候碰到iframe 跨域自适应的问题

刚开始很迷惑开心网那边技术工程师给我发了一段这样子的代码

<body onload="javascript: setHeight();">
<script>
function setHeight(){
   var dHeight = document.documentElement.scrollHeight;
   var t = document.createElement("div");
   t.innerHTML = '<iframe id="kxiframeagent"
src="http://xxxx.kaixin001.com/xxx/xxx.html#'+dHeight+'"
scrolling="yes" height="0px" width="0px"></iframe>';
   document.documentElement.appendChild(t.firstChild);
}
</script>

我想着跨域如何解决啊!后来去网上搜索了一下子恍然大悟

具体如下我是复制过来了大家重点理解一下子它的实现思路：

iframe跨域自适应

问题:

A域名下的页面a.htm中通过iframe嵌入B域名下的页面b.html,由于b.html的大小等是不可预知而且会变化的,所以需要 a.htm中的iframe自适应大小.

问题本质 :

js的跨域问题,因为要控制a.htm中iframe的大小就必须首先读取得到b.html的大小,A、B不属于同一个域,js的访问受限,读取不到b.html的大小.

解决方案:

首先前提是A，B是合作关系,b.html中能引入A提供的js

首先a.html中通过iframe引入了b.html
Html代码

    1 . < iframe id = " aIframe " height = " 0 " width = " 0 "
    2 . src = " http://www.b.com/html/b.html " frameborder = " no " border = " 0px " marginwidth = " 0 "
    3 . marginheight = " 0 " scrolling = " no " allowtransparency = " yes " >< / iframe>

< iframe id = " aIframe " height = " 0 " width = " 0 "
src = " http://www.b.com/html/b.html " frameborder = " no " border = " 0px " marginwidth = " 0 "
marginheight = " 0 " scrolling = " no " allowtransparency = " yes " >< / iframe>

B在b.html中引入了A提供的js文件
Html代码

    1 . < script language = " javascript " type = " text/javascript " src = " http://www.a.com/js/a.js " >< / script>

< script language = " javascript " type = " text/javascript " src = " http://www.a.com/js/a.js " >< / script>

该js首先读取b.html的宽和高,然后创建一个iframe,src为和A同一个域的中间代理页面a_proxy.html,吧读取到的宽和高设置到src的hash里面
Html代码

    1 . < iframe id = " iframeProxy "   height = " 0 " width = " 0 "   src = " http://www.a.com/html/a_proxy.html#width|height " style = " display:none " >< / iframe>

< iframe id = " iframeProxy "   height = " 0 " width = " 0 "   src = " http://www.a.com/html/a_proxy.html#width|height " style = " display:none " >< / iframe>

a_proxy.html是A域下提供好的中间代理页面,它负责读取location.hash里面的width和height的值,然后设置与它同域下的a.html中的iframe的宽和高.
Js代码

    1 . var pParentFrame = parent.parent.document.getElementById( " aIframe " );
    2 . var locationUrlHash =
    3 .                  parent.parent.frames[ " aIframe " ].frames[ " iframeProxy " ].location.hash;
    4 . pParentFrame.style.width = locationUrlHash.split( " # " )[ 1 ].split( " | " )[ 0 ] + " px " ;
    5 . pParentFrame.style.height = locationUrlHash.split( " # " )[ 1 ].split( " | " )[ 1 ] + " px " ;

var pParentFrame = parent.parent.document.getElementById( " aIframe " );
var locationUrlHash =
                 parent.parent.frames[ " aIframe " ].frames[ " iframeProxy " ].location.hash;
pParentFrame.style.width = locationUrlHash.split( " # " )[ 1 ].split( " | " )[ 0 ] + " px " ;
pParentFrame.style.height = locationUrlHash.split( " # " )[ 1 ].split( " | " )[ 1 ] + " px " ;

这样的话a.html中的iframe就自适应为b.html的宽和高了.

js跨域有关问题之跨域iframe自适应大小

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