I am attempting to toggle the height of all elements with class name on button click.

Here is what I am currently using. Right now it will work onClick the first time, but wont change back on second click. When I change if statement to something NOT true, the function still fires.

```
<head>
<script type="text/javascript">
function changeHeight() {
var elems = document.getElementsByClassName('div1');
for(var i = 0; i < elems.length; i++) 
{
if (elems[i].style.height = '25px'){
    elems[i].style.height = '110px';
    }
else {
      elems[i].style.height = '25px';
      document.getElementById("expand").innerHTML="[+]";
}
</script>

<style type="text/css">
.div1 {
    overflow:hidden;
    height:25px;
}
</script>

</head>

<body>
<button type="button" id="expand" onClick="changeHeight();">[+]</button>
    <div class="div1">
        content
    </div>
    <div class="div1">
        content
    </div>
</body>

```

I believe the issue is I can not get my 'else' to fire because my if is not firing properly.
Any ideas?

Thanks
-Trevor