Can not get function to fire

[lawrence]

I'm trying to modify a script to work on my site, but I can figure out
how to call it. I've two lines of PHP printing out this bit of a form:

echo "<input type=\"file\" name=\"uploadedFile\">";
echo "<input type=\"hidden\" name=\"uploadType\" value=\"image\"
onchange=\"DoPreview();\">";
This function is listed above the form. is onchange() the correct
trigger?

<script language="javascript">
function DoPreview()
{
var filename = document.forms[0].inputId1.value;
var Img = new Image();
if (navigator.appName == "Netscape")
{
alert("Previews do not work in Netscape.");
}
else
{
Img.src = filename;
ppImg = Img.src;
alert("You're loading image" + ppImg);
document.images[0].src = Img.src;
}
}
</script>

[Matt Kruse]

lawrence wrote:

echo "<input type=\"hidden\" name=\"uploadType\" value=\"image\"
onchange=\"DoPreview();\">";

Hidden inputs do not have an onChange event, since the user can't change the
value manually.
In whatever code triggers the population of this form field, also call the
DoPreview() function.

--
Matt Kruse
Javascript Toolbox: http://www.JavascriptToolbox.com/