How do I get form data for validating forms

I have created a form with 5 text field for users to enter information. I want to validate my form before I send it to my server. When I search for how to validate forms using javascript it only comes up with how to validate 1 text field of the form. Since I have 5 fields I need a way of validating more then one field. How could I do that or how to do get the value in javascript of 1 of the form objects? I know there is a .value script but it doesn't seem to work with more than 1 form object.

My javascipt looks something like this:

<script type="text/javascript">
function validate_newuser_form(form)
{
with (form)
{
if (username.value==null||username.value=="")
{
username.focus();return false; alert("User name validation failed, please enter a value!");
}
else
{
return true;
}
}
}
</script>

and the html form looks like this:

<form action="" onsubmit="return validate_newmember_form(this)" method="post" name="newuser" dir="ltr">
<input name="username" type="text" id="username" value="" size="31" maxlength="30" />
<input name="newpassword" type="text" id="newpassword" size="21" maxlength="20" />
<input name="confirmpassword" type="text" id="confirmpassword" size="21" maxlength="20" />
<input name = "submit" type="submit" id="submit"/>
</form>

Thanks.

~Imozeb

 

There is no need to pass this to your function. Javascript can pull out any variable using getElementByID assuming of course that your tag has a unique id. Fortunately you do.

<script>
function validate_newmember_form() {
var username = document.getElementById("username").value;
var newpassword = document.getElementById("newpassword").value;
var confirmpassword = document.getElementById("confirmpassword").value;
if (username == "") {
alert("You have not entered a user name");
return false;
}
if (newpassword != confirmpassword) {
alert("Your passwords do not match");
return false;
}
}

<form action="" onsubmit="return validate_newmember_form()" method="post" name="newuser" dir="ltr">
<input name="username" type="text" id="username" value="" size="31" maxlength="30" />
<input name="newpassword" type="text" id="newpassword" size="21" maxlength="20" />
<input name="confirmpassword" type="text" id="confirmpassword" size="21" maxlength="20" />
<input name = "submit" type="submit" id="submit"/>
</form>

 

Thanks harrierdh.

~Imozeb