Can PHP invoke the Javascript Argument?

[Anon]

I create a form include first name,last name,E-mail such as and after user submit,I woulk like to verify the required field.I want to write a php function embedded in the javascript validation function to check whether every field are correct.I pass two arguments to the javascript function.One is the field name,another is the field label.How can php get these two arguments? Or if have some other way to realize this ?

[Anon]

Im a bit confused why you want to use javascript to validate form fields when you can just do it in PHP? If you want fields to be required, in your code just put something like

if ($var != '')
{
do something good
}
else
{
print error
}

[Anon]

For I want to focus on the required field.so I have to use javascript document.form.field.focus().For there are so many fields to be check.I just want to write a function like that:
Function checkString(field,field_label)
{ if (trim($field) == ''))
{ echo "document.form.$field_label.focus();";
echo "alert(\"$field_label must have value \");"
}
}

unfortunately,it doesn't work.PHP doesn't recognize the javascript argument.

[Anon]

You can do it all in javascript.

<SCRIPT LANGUAGE="JavaScript">
<!--

Function checkString(field,field_label)
{
trimmed = field.replace(/ /gi,""); // remove spaces

if (trimmed.length==0){
document.form.field_label.focus();
alert(field_label+" must have value");
}
}
//-->
</SCRIPT>