The “toggle_visibility” function specifies (eng, met), not (var1, var2), so it seems not to matter what order of parameters you send it, it’s going to read (eng, met) always.

function toggle_visibility(eng, met) {
var e1 = document.getElementById(eng);
var e2 = document.getElementById(met);
if(e1.style.display == ‘block’) {
e1.style.display = ‘none’;
e2.style.display = ‘block’;
} else {
e1.style.display = ‘block’;
e2.style.display = ‘none’;
}

You actually don’t have to pass div objects to toggle_visibility.

The script below works for me.

1) I put quotes around the getElementById arguments “eng” and “met”
2) I removed arguments from toggle_visibility and its call

function toggle_visibility()
{
var e1 = document.getElementById(“eng”);
var e2 = document.getElementById(“met”);
if(e1.style.display == ‘block’)
{
e1.style.display = ‘none’;
e2.style.display = ‘block’;
}
else
{
e1.style.display = ‘block’;
e2.style.display = ‘none’;
}
}

<div id=“eng” style=“display: block;”>
This is English<br />
<a href=”#” onclick=“toggle_visibility();”>Convert to Metric</a>
</div>
<div id=“met” style=“display: none;”>
This is Metric<br />
<a href=”#” onclick=“toggle_visibility();”>Convert to English</a>
</div>

@jaytkay That does it. Works like a charm. Thanks.

@CWOTUS That’s the scripting solution to what you were pointing out. Thanks.