Help with setting form enctype with javascript

[stewartalan]

I have a form that is sent to a javascript function that first determines if a file has been selected to upload along with it. If there is a file the form is sent to one page with a multipart/form-data enctype and if there is no file then it is sent elswhere witout this enctype.

My Function is thus

function filechecker() {
if (document.FormName.file.value == "&quot
{
document.FormName.action = "page1.asp";
document.FormName.encoding = "text/html";
document.FormName.method = "POST"
}else{
document.FormName.action = "page2.asp";
document.FormName.encoding = "multipart/form-data";
document.FormName.method = "POST"
}
document.FormName.submit();
}

This does not work and I get a javascript error when trying to submit the form that says 'Could not get the encoding property. Invalid Arguement'

Can anyone tell me where I am going wrong??

Thanks

Stewart