Please help me. The validation is notworking
<script type="text/javascript" src="javascript.js">
function validation()
{
var fname=document.forms["form1"]["fname"].value;
var lname=document.forms["form1"]["lname"].value;
var idnumber=document.forms["form1"]["idnumber"].value;
var email=document.forms["form1"]["email"].value;
var atpos=email.indexOf("@");
var dotpos=email.lastIndexOf(".");
var address=document.forms["form1"]["address"].value;
var phonenumber=document.forms["form1"]["phonenumber"].value;
if (fname==null || fname=="")
{
alert("Name should be entered correctly");
return false;
}
if (lname==null || lname=="")
{
alert("Name should be entered correctly");
return false;
}
if (isNaN(idnumber))
{
alert("Please enter a valid id number");
return false;
}
if (atpos<1 || dotpos<atpos+2 || dotpos+2>=x.length)
{
alert("Please enter a valid e-mail address");
return false;
}
if(address==null || address=="")
{
alert("Please insert your address");
return false;
}
if (isNaN(phonenumber))
{
alert("Please enter a valid phone number");
return false;
}
}
</script>
<form name="form1" action="validation.php" method="post" onsubmit=" return validation(this);return false">
Firstname:<input type="text" name="fname"><br/>
Lastname:<input type="text" name="lname"><br/>
Nation ID Number:<input type="text" name="idnumber" minlength="8"maxlength="8"><br/>
Email address: <input type="text" name="email"><br/>
Address:<input type="text" name="address"><br/>
Pnone number:<input type="text" name="phonenumber"><br/>
<input type="reset" name="reset" value="reset">
<input type="submit" name="submit" value="submit">
</form>
There are a number of issues with that code:
You really should not use the same <script>
element for both calling src="javascript.js"
and at the same time declare a function. Use separate elements, like this:
<script type="text/javascript" src="javascript.js"></script> <script type="text/javascript"> function validation() { ... } </script>
In the <form>
element, there's a redundant ;return false
. The form will take the value from return validation(this)
, anything after it will be ignored. Also, no need of ";" when using in-line javascript.
You are passing passing this
as argument to the validation()
function, but validation is expecting no argument. Should be:
function validation(oForm)
If you are already passing this
, why not use it? this
is a reference to the element itself, so it is, for the validation function, a reference to the form. So no need to name the form.
<form action="validation.php" method="post" onsubmit="return validation(this)">
And the references in function would be:
function validation(oForm)
{
var fname=oForm["fname"].value;
var lname=oForm["lname"].value;
}
Those changes alone could solve your problem. I'll check the code further to see if there is something else.
EDIT:
I've tested the validation now, and it works. The only required modification is removing the scr=validation.js
from your <SCRIPT>
tag. Use separate tags for that, as i suggested.
But i strongly suggest you consider the other issues I've mentioned.
Also, other suggestions regarding the validation itself:
For alphanumerical fields, no need to check for null
, only "" is enough. You can simply use:
if (lname=="")
First Name and Last Name error messages are the same. That will confuse users.
Avoid testing phone numbers as numeric. Remember "(407) 234-5678" is a perfectly valid phone number, although it will fail your test. Unless you have a strong reason to treat it as numeric (automatic dialing?), leave it as an ordinary, text field.
In the National ID field: There is no minlength
in HTML. Only maxlength
isNaN(idnumber)
will return true
if value is blank. And also if length<8. I assume it is a required field with a required length, so you should use:
if (isNaN(idnumber) || idnumber.length != 8) { alert("Please enter a valid id number"); return false; }
For all your tests, consider trimming the values. Currently, input like " " (blanks only) WILL pass your test. Javascript has no built-in trim function, but it can be done with this:
function trim( texto ) {
return texto.replace(/^\\s*|\\s*$/g, "");
}
And used like this:
var fname=trim(oForm["fname"].value);
return true;
in validation()
after all tests successful. Here is the suggested code after all changes:
<script type="text/javascript" scr="validation.js"></script>
<script type="text/javascript">
function validation(oForm)
{
var fname = trim(oForm["fname"].value);
var lname = trim(oForm["lname"].value);
var idnumber = trim(oForm["idnumber"].value);
var email = trim(oForm["email"].value);
var atpos = email.indexOf("@");
var dotpos = email.lastIndexOf(".");
var address = trim(oForm["address"].value);
var phonenumber = trim(oForm["phonenumber"].value);
if (fname=="")
{
alert("First name should be entered");
return false;
}
if (lname=="")
{
alert("Last name should be entered");
return false;
}
if (isNaN(idnumber) || idnumber.length != 8)
{
alert("Please enter a valid id number");
return false;
}
if (atpos<1 || dotpos<atpos+2 || dotpos+2>=x.length)
{
alert("Please enter a valid e-mail address");
return false;
}
if(address=="")
{
alert("Please insert your address");
return false;
}
if (isNaN(phonenumber))
{
alert("Please enter a valid phone number");
return false;
}
return true;
}
function trim( texto ) {
return texto.replace(/^\s*|\s*$/g, "");
}
</script>
<form name="form1" action="validation.php" method="post" onsubmit="return validation(this)">
Firstname:<input type="text" name="fname"><br/>
Lastname:<input type="text" name="lname"><br/>
Nation ID Number:<input type="text" name="idnumber" maxlength="8"><br/>
Email address: <input type="text" name="email"><br/>
Address:<input type="text" name="address"><br/>
Pnone number:<input type="text" name="phonenumber"><br/>
<input type="reset" name="reset" value="reset">
<input type="submit" name="submit" value="submit">
</form>
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