静态iframe异步加载

tab选项卡中内容过多时候用到的iframe。

<ul id="nav_ul">
    <li>第一个iframe</li>
    <li>第二个iframe</li>
    <li>第三个iframe</li>
</ul>
<div class="iframe_cont"></div>
<div class="iframe_cont"></div>
<div class="iframe_cont"></div>
<script type="text/javascript">
(function(){
//取class数组
function getElementsByClass(searchClass,node,tag) {
    var classElements = new Array();
    if ( node == null )
        node = document;
        if ( tag == null )
            tag = '*';
            var els = node.getElementsByTagName(tag);
            var elsLen = els.length;
            var pattern = new RegExp("(^|\\s)"+searchClass+"(\\s|$)");
            for (i = 0, j = 0; i < elsLen; i++) {
            if ( pattern.test(els[i].className) ) {
                classElements[j] = els[i];
                j++;
        }
    }
    return classElements;
}
var liArr = document.getElementById('nav_ul').getElementsByTagName('li'),
    contArr = getElementsByClass('iframe_cont'),
    len = liArr.length,
    flagArr = new Array(len);
//初始化
function init(){
    for(var i = 0; i < len; i++){
        flagArr[i] = false;
    }
    contArr[0].style.display = 'block';
    flagArr[0] = true;
    contArr[0].innerHTML = '<iframe src=\"iframe1.html\" width=\"1002\" height=\"1128\" frameborder=\"0\" scrolling=\"no\" allowtransparency=\"true\"></iframe>'
}
init();
//点击切换
for(var j = 0; j < len; j++){(function(j){
        liArr[j].onclick = function(){
            for(var k = 0; k < len; k++){
                contArr[k].style.display = 'none';        
            }
            contArr[j].style.display = 'block';    
            if (flagArr[j] == false){
                flagArr[j] = true;
                contArr[j].innerHTML = '<iframe src=\"iframe' + (j+1) + '.html\" width=\"1002\" height=\"1128\" frameborder=\"0\" scrolling=\"no\" allowtransparency=\"true\"></iframe>'
            }
        }
    })(j)    
}
})();
</script>