Ifram框架自适应内容的高度（代码简单易懂ie7,8,9,火狐，谷歌都测试通过）

ifram框架自适应内容的高度这个是长期困扰我的一个问题，今天有时间又把之前的代码拿出来研究了下，刚好最近我在做一个项目，经常用到ｊｑ的写法，举一反三，让我找到了方法：

 

这个是之前网上找的，只能支持ｉｅ7：代码如下

<script language="javascript">
        function setcwinheight()//自动拉伸
        {
            var xsun = document.getelementbyid("main"); //iframe id
            if (document.getelementbyid) {
                if (xsun && !window.opera) {
                    if (xsun.contentdocument && xsun.contentdocument.body.offsetheight) {
                        xsun.height = xsun.contentdocument.body.offsetheight + 20;
                    } else if (xsun.document && xsun.document.body.scrollheight) {
                        xsun.height = xsun.contentdocument.body.offsetheight + 20;
                    }
                }
            }
        }
    </script>

 

我修改后的代码：

<script language="javascript">
        function setcwinheight()//自动拉伸
        {
            var xsun = document.getelementbyid("main"); //iframe id
            //var h1 = xsun.contentdocument.body.offsetheight;
            var h2 = document.documentelement.offsetheight;
            if (document.getelementbyid) {
                if (xsun && !window.opera) {
                    if (xsun.contentdocument && h2) {
                        xsun.height = h2 + 20;
                    } else if (xsun.document && xsun.document.body.scrollheight) {
                        xsun.height = h2 + 20;
                    }
                }
            }
        }
    </script>

应该能很清楚的看到区别在哪里，就是var h1 = xsun.contentdocument.body.offsetheight;
                                                                    var h2 = document.documentelement.offsetheight;

h1取出来的高度都为0，h2才是正确高度。具体含义自己去百度下就知道两者的区别了

调用方法：

<iframe frameborder="0" id="main" name="main" onload="javascript：setcwinheight();"
                        src="xsun.html" marginwidth="0" marginheight="0" scrolling="no" style="z-index: 1;
                        width: 100%; min-height: 300px;"></iframe>