Perhaps someone can offer some assistance with some Javascript I placed in a web page. The purpose is to ensure that content has been entered in certain fields of an email form. This was done to avoid getting empty forms if someone clicks Submit without entering anything. Instead, they will be prompted to enter the required fields. I don't think this is a problem of a pop-up being blocked by FF because I get no alert that a pop-up is being blocked.

The Javascript code is:

<script language="javascript"
type="text/javascript">

<!-- hide script from older browsers
function validateForm(contact)
{

if(""==document.forms.contact.LastName.value)
{
alert("Please enter your last name.");
return false;
}

if(""==document.forms.contact.email.value)
{
alert("Please enter your email address.");
return false;
}

if(""==document.forms.contact.questions.value)
{
alert("Please enter your question or comment.");
return false;
}

}
stop hiding script -->
</script>


The <form> tag is :
<form name="contact" method="post" action="_gdForm/webformmailer.asp"
onSubmit="return validateForm(contact);">


Thanks in advance for your help.

Correct, popup blockers don't block alert boxes.

In the script, try adding a "return true" after the last IF condition.

----------

Probably just side-notes:


Since the function doesn't use the "contact" parameter in the function call, you might as well remove it:


If you did use it, it should be quoted:

So should that.

Hi Pandy and Christian, Unfortunately, the changes you suggested didn't work. Of course, I may have made an error entering them - I know nothing about JavaScript, so I may have placed the statement in the wrong place or have the syntax wrong. FF still sends the empty form.

Here's the modified code.

<!-- hide script from older browsers
function validateForm(contact)
{

if(""==document.forms.contact.LastName.value)
{
alert("Please enter your last name.");
return false;
}

if(""==document.forms.contact.email.value)
{
alert("Please enter your email address.");
return false;
}

if(""==document.forms.contact.questions.value)
{
alert("Please enter your question or comment.");
return false;
}
return true;
}
stop hiding script -->
</script>


And the <form> tag.

<form name="contact" method="post" action="_gdForm/webformmailer.asp"
onSubmit="return validateForm();">

This part:


needs a "//" before, if it's used at all (using HTML comments to hide from old browsers is not necessary anymore, since the browsers in question are long gone). So try something like:

It was a minimal test case!

Excuse me, but shouldn't the following not be the other way around?

not:
if(""==document.forms.contact.LastName.value)

but:
if(document.forms.contact.LastName.value=="")

etc.

I don't think it matters in this case (and my browsers agree), but I haven't found any specs saying so.

With other operators like "=" or "<" the order does matter, of course.

It looks very funny, but equality is commutative. A=B iff B=A. (That's the = of logic, of course, not the (inappropriate, IMO) assignment operator.) I suppose in principle one could design a programming language in which equality was (subtly) non-commutative, but it doesn't sound very likely.

Christian, that seems to have been the problem. I removed the HTML comment tags and the script works fine in FF now. Thanks so much for your help. And thanks to everyone who offered help with this simple problem. This is a great forum, particularly for dummies like me who sometimes get in over our heads!