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  Form Validation
Subject:   java script form validation
Date:   2009-03-18 12:09:51
From:   mimito
How can icplace thecursor in appropriae form elemen,

for instance i type wrong email address and i receive alert"please enter the valid email address and i click OK, i want the cursor back to the email address field, but that is not happening , please help.

this my code

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">


<script language="JavaScript">

function checkForm(form)
//create for loop
//var len = form.elements.length;
var myForm = document.getElementById("myForm");
var len = myForm.elements.length;
var i=0;

for (i=0; i < len-2; i++)
var fieldname = myForm.elements[i].value;


alert("The " + fieldname +" field is required.");
return false;


return true;


function emailTest(emailText)
var email = emailText.value;
var emailPattern = /^.+@.+\..{2,}$/;
if (!(emailPattern.test(email))) {
alert("Please enter a valid email address.");

function phoneTest(phoneText)
var phone =phoneText.value;
//this is a Regular Expression to pattern match a phone number
var phonePattern = /^\({0,1}[0-9]{3}\){0,1}[ \-\.]{0,1}[0-9]{3}[ \-\.]{0,1}[0-9]{4}$/;
if (!(phonePattern.test(phone))) {
alert("Provide a valid phone number. (xxx)xxx-xxxx");
return false;
return true;

function faxTest(faxText)
var fax =faxText.value;
//this is a Regular Expression to pattern match a phone number
var faxPattern = /^\({0,1}[0-9]{3}\){0,1}[ \-\.]{0,1}[0-9]{3}[ \-\.]{0,1}[0-9]{4}$/;
if (!(faxPattern.test(fax))) {
alert("Provide a valid fax number. (xxx)xxx-xxxx");
return false;
return true;

// -->

<h3>Assignment 2 Form</h3>

<form name id="myForm" method="post"

<input size="30" name="name" type="text">

Email address:

<input size="30" name="email address" onblur="emailTest(this);" type="text">

Phone number:

<input size="30" name="phone number" onblur="phoneTest(this);" type="text">

Fax number:

<input size="30" name="fax number" onblur="faxTest(this);" type="text">

<input value="Submit Data" onclick="return checkForm(this.form);" type="submit">
<input value="Reset Form" type="reset">