expanding and collapsing folders

问题:

I need to get more than one element to toggle open and closed. Right now the function is just selecting the ID, but I'd like to know how to get it to select a class. I thought I could change the document.getElementById to document.getElementByClass but that didn't work.

I picked this bit of code during my search:

#ToggleTarget {display:hidden;}

<script type="text/javascript">
function Toggle() {
    var el = document.getElementById("ToggleTarget");
    if (el.style.display == "block") {
        el.style.display = "none";
    }
    else {
        el.style.display = "block";
    }
}
</script>

回答1:

var getElementsByClassName = function(node, classname) {
    if (document.getElementsByClassName) { 
        return document.getElementsByClassName(classname);
    }
    var a = [];
    var re = new RegExp('(^| )'+classname+'( |$)');
    var els = node.getElementsByTagName("*");
    for(var i=0,j=els.length; i<j; i++)
        if(re.test(els[i].className))a.push(els[i]);
    return a;
}

var Toggle = function(){
    var tp = getElementsByClassName(document.documentElement,'toggle');
        for(var i = 0; i < tp.length; i++){
            if(tp[i].style.display=='none')
                tp[i].style.display='block'
            else
                tp[i].style.display='none'
    }
}

Use getElementsByClassName and then loop through them.

EDIT

Just make sure they have the class toggle as used in my code above.

UPDATE

Added function for IE support (adopted from https://stackoverflow.com/a/7410966/600101).