Javascript Form Validation check - javascript

I am doing some homework about form validation and have write some code but it is not valid with some problems. Can someone tell me what's wrong in them and fix them? Thanks
function formCheck() {
var form = document.forms["contact_form"];
if(form["first_name"]["last_name"].value == "") {
alert("Please fill in the required name.");
form["first_name"]["last_name"].focus();
return false;
}
var zip = /^\d{5}(-\d{4})?$/.test;
if(zip.test(form["zip_code"]).value == false){
alert("Please fill in a valid zipcode.");
form["zip_code"].focus();
return false;
}
var phone = /^\[0-9]{10}$|^\([0-9]{3}\)[ ]?[0-9]{3}-[0-9]{4}$/
if(phone.test(form["phone_number"]).value == false){
alert("Phone number input format is not valid.");
form["phone_number"].focus();
return false;
}
var email = /^([a-zA-Z0-9_.])+#[a-zA-Z0-9]([a-zA-Z0-9])+\.([a-z])+$/
if(email.test(form["email_address"].value == false){
alert("Email format is not valid.");
return false;
}
form.submit();
return true;
}

This seems incorrect:
if(form["first_name"]["last_name"].value == "") {
alert("Please fill in the required name.");
form["first_name"]["last_name"].focus();
return false;
}
You may want to replace that with:
if(form["first_name"].value == "") {
alert("Please fill in the required first name.");
form["first_name"].focus();
return false;
}
if(form["last_name"].value == "") {
alert("Please fill in the required last name.");
form["last_name"].focus();
return false;
}

Related

javascript validating in the wrong order

function validateForm() {
var name = document.forms["myForm"]["name"].value;
if (name == undefined || name == null || name == "") {
alert("Name must be filled out");
return false;
}
var letters = /^[A-Za-z]+$/;
if (name.match(letters)) {
return true;
} else {
alert('Name must have alphabet characters only');
document.forms["myForm"]["name"].focus();
return false;
}
}
function validateForm() {
var unit = document.forms["myForm"]["unit"].value;
if (unit == undefined || unit == null || unit == "") {
alert("Unit must be filled out");
return false;
}
var alpha = /^[0-9a-zA-Z]+$/;
if (unit.match(alpha)) {
return true;
} else {
alert('User address must have alphanumeric characters only');
document.forms["myForm"]["unit"].focus();
return false;
}
}
The validation works but it starts from the unit field instead of the name, when I fill out the unit field with the right characters and submit it doesn't go back to validate the Name field, please need serious advice?
You cannot have 2 functions with the same name as the second one will override the first. Merge the functions like so:
function validateForm() {
var formIsValid = true;
var name = document.forms["myForm"]["name"].value;
if (name == undefined || name == null || name == "") {
alert("Name must be filled out");
formIsValid = false;
} else if (!name.match(/^[A-Za-z]+$/)) {
alert('Name must have alphabet characters only');
document.forms["myForm"]["name"].focus();
formIsValid = false;
}
var unit = document.forms["myForm"]["unit"].value;
if (unit == undefined || unit == null || unit == "") {
alert("Unit must be filled out");
formIsValid = false;
} else if (!unit.match(/^[0-9a-zA-Z]+$/)) {
alert('User address must have alphanumeric characters only');
document.forms["myForm"]["unit"].focus();
formIsValid = false;
}
return formIsValid;
}

How to I validate a password using regular expressions in javascript?

This is my code. It functions perfectly up to the password validation. It completely ignores my null test and goes straight to the actual validation but then refuses to go past it and keeps giving me my invalid password alert. Any ideas as to how to fix this issue?
function validate(){
var l = document.getElementById('lname').value;
var f = document.getElementById('fname').value;
var e = document.getElementById('email').value;
var e2 = document.getElementById('cemail').value;
var u = document.getElementById('newuser').value;
var p = document.getElementById('newpass');
var p2 = document.getElementById('cnewpass');
var str = new RegExp(/[a-zA-Z]{1,30}$/);
var em = new RegExp(/[a-z0-9._-]+#[a-z]+\.[a-z]{1,30}$/);
var pass = new RegExp(/[a-zA-Z0-9]{1,15}$/);
if (l == null || l == ""){
alert("Please enter your last name");
return false;
}
var ln = str.test(l);
if(ln==false){
alert("Invalid Name.");
documents.forms['registration']['lname'].focus;
return false;
}
if (f == null || f == ""){
alert("Please enter your first name");
return false;
}
var fn = str.test(f);
if(fn==false){
alert("Invalid Name.");
documents.forms['registration']['fname'].focus;
return false;
}
if (e == null || e == "") {
alert("Please enter an email address");
return false;
}
if (e2 == null || e2 == "") {
alert("Please enter an email address");
return false;
}
var eml = em.test(e);
if(eml==false){
alert("Invalid Email.");
documents.forms['registration']['email'].focus;
return false;
}
var eml2 = em.test(e2);
if(eml2==false){
alert("Invalid Email.");
documents.forms['registration']['cemail'].focus;
return false;
}
if(e2!=e){
alert("Please ensure that the emails match.");
return false;
}
if (u == null || u == "") {
alert("Please enter a user name");
return false;
}
var un = str.test(u);
if(un==false){
alert("Invalid user name");
documents.forms['registration']['newuser'].focus;
return false;
}
if (p == null || p == "") {
alert("works");
alert("Please enter a password");
return false;
}
if (p2 == null || p2 == "") {
alert("Please enter a password");
return false;
}
var pwrd = pass.test(p);
if(pwrd==false){
alert("Invalid Password.");
documents.forms['registration']['newpass'].focus;
return false;
}
if(p2!=p){
alert("Please ensure that the passwords match");
documents.forms['registration']['cnewpass'].focus;
return false;
}
}
You should amend js code that retriving data from from. Look,
var p = document.getElementById('newpass');
var p2 = document.getElementById('cnewpass');
Here You are trying to get NOT values of input tags, you are trying to get tag.
So You should replace above code with:
var p = document.getElementById('newpass').value;
var p2 = document.getElementById('cnewpass').value;
I hope it will help you
You should pass the value of password fields.
try changing the code to
var p = document.getElementById('newpass').value;
var p2 = document.getElementById('cnewpass').value;

How to validate multi-functions using Javascript in .asp

I am attempting to validate 6 functions on a form. I am getting the appropriate alerts set for each function but the form does not seem to be validating correctly and is submitting the form when the 'Generate' button is pressed.
I would be extremely grateful for any advice on this
This is how I have it set at present:
function ValidateFields(){
//Validate all Required Fields
if (RequiredTextValidate()&& CheckDateTime()&& ReasonAbsenceValidate()&&
ReturnDateChanged() && FirstDateChanged() && ActualDateChanged())return true;
}
<script type="text/javascript" language="Javascript">
function RequiredTextValidate() {
//check all required fields are completed
if (document.getElementById("<%=CompletedByTextBox.ClientID%>").value == "") {
alert("Completed by field cannot be blank");
document.getElementById("<%=CompletedByTextBox.ClientID%>").focus();
return false;
}
if (document.getElementById("<%=CompletedExtTextBox.ClientID %>").value == "") {
alert("Completed By Extension field cannot be blank");
document.getElementById("<%=CompletedExtTextBox.ClientID %>").focus();
return false;
}
if (document.getElementById("<%=EmployeeNoTextBox.ClientID %>").value == "") {
alert("Employee No field cannot be blank");
document.getElementById("<%=EmployeeNoTextBox.ClientID %>").focus();
return false;
}
if (document.getElementById("<%=EmployeeNameTextBox.ClientID %>").value == "") {
alert("Employee Name field cannot be blank");
document.getElementById("<%=EmployeeNameTextBox.ClientID %>").focus();
return false;
}
return true;
}
function CheckDateTime() {
// regular expression to match required date format
re = /^\d{1,2}\/\d{1,2}\/\d{4}$/;
if (document.getElementById("<%=SickDateTextBox.ClientID %>").value != '' && !document.getElementById("<%=SickDateTextBox.ClientID %>").value.match(re)) {
alert("Invalid date format: " + document.getElementById("<%=SickDateTextBox.ClientID %>").value);
document.getElementById("<%=SickDateTextBox.ClientID %>").focus();
return false;
}
// regular expression to match required time format
re = /^\d{1,2}:\d{2}([ap]m)?$/;
if (document.getElementById("<%=SickTimeTextBox.ClientID %>").value != '' && !document.getElementById("<%=SickTimeTextBox.ClientID %>").value.match(re)) {
alert("Invalid time format: " + document.getElementById("<%=SickTimeTextBox.ClientID %>").value);
document.getElementById("<%=SickTimeTextBox.ClientID %>").focus();
return false;
}
return true;
}
function ReasonAbsenceValidate() {
//check that reason for absence field is completed
if (document.getElementById("<%=ReasonTextBox.ClientID%>").value == "") {
alert("Reason for absence field cannot be blank");
document.getElementById("<%=ReasonTextBox.ClientID%>").focus();
return false;
}
return true;
}
function ReturnDateChanged() {
// check that either Return date or Date Unknown fields are completed
var ReturnDateValid = document.getElementById("<%=ReturnDateTextBox.ClientID%>").value;
var ReturnDateUnknown = document.getElementById("<%=ReturnUnknownCheckBox.ClientID%>").checked;
if (ReturnDateUnknown.checked)
{
ReturnDateValid.disabled = false;
ReturnDateUnknown.disabled = "disabled";
}
if (ReturnDateValid == "" && ReturnDateUnknown == "") {
alert("You must enter at least one field for anticipated return");
return false;
}
return true;
}
function FirstDateChanged() {
// check that either First date of sickness or Date Unknown fields are completed
var FirstDateValid = document.getElementById("<%=FirstDateTextBox.ClientID%>").value;
var FirstDateUnknown = document.getElementById("<%=FirstDateUnknownCheckBox.ClientID%>").checked;
if (FirstDateUnknown.checked)
{
FirstDateValid.disabled = false;
FirstDateUnknown.disabled = "disabled";
}
if (FirstDateValid == "" && FirstDateUnknown == "") {
alert("You must enter at least one field for first day of sickness");
return false;
}
return true;
}
function ActualDateChanged() {
// check that either Actual date of return or Date Unknown fields are completed
var ActualDateValid = document.getElementById("<%=ActualDateTextBox.ClientID%>").value;
var ActualDateUnknown = document.getElementById("<%=ActualDateUnknownCheckBox.ClientID%>").checked;
if (ActualDateUnknown.checked)
{
ActualDateValid.disabled = false;
ActualDateUnknown.disabled = "disabled";
}
if (ActualDateValid == "" && ActualDateUnknown == "") {
alert("You must enter at least one field for actual date of return");
return false;
}
return true;
}
function ValidateFields(){
//Validate all Required Fields
if (RequiredTextValidate()&& CheckDateTime()&& ReasonAbsenceValidate()&&
ReturnDateChanged() && FirstDateChanged() && ActualDateChanged())return true;
}
</script>
update function like following:
You need to return flase in case of invalid input to prevent form from being posted.
function ValidateFields() {
//Validate all Required Fields
if (RequiredTextValidate() && CheckDateTime() && ReasonAbsenceValidate() && ReturnDateChanged() && FirstDateChanged() && ActualDateChanged()) {
return true;
} else {
return false;
}
}
Update
if (document.getElementById("<%=SickTimeTextBox.ClientID %>").value != '' &&
!document.getElementById("<%=SickTimeTextBox.ClientID %>").value.match(re))
condition seems to be wrong. It should be like following.
if (document.getElementById("<%=SickTimeTextBox.ClientID %>").value == '' &&
!document.getElementById("<%=SickTimeTextBox.ClientID %>").value.match(re))
Use == instead of != operator.

Javascript Email Validation from Form Field suddenly doesn't work?

Working on a web page which used to have a working email validation, but after adding in a few additional features it suddenly no longer works. The page shouldn't proceed unless all fields are valid, everything is basically client-side if you're wondering why it's a bit of a weird website.
Originally the e-mail validation worked for if the field was blank or did not have an '#' and '.' following it, using the code:
if (d==null || d=="")
{
document.forms["registration"]["email"].focus();
alert("Please enter your email address");
return false;
}
else
{
var emailAddress = d;
var atLoc = emailAddress.indexOf("#",1);
var dotLoc = emailAddress.indexOf(".",atLoc+2);
var len = emailAddress.length;
if (atLoc > 0 && dotLoc > 0 && len > dotLoc+2)
{
return true;
}
else
{
alert("Invalid E-mail address format! Please enter your e-mail address again.");
document.forms["registration"]["email"].focus();
return false;
}
}
However, added with the entire code of:
function validateForm(){
{
var f=document.forms["registration"]["FirstName"].value;
var a=document.forms["registration"]["Surname"].value;
var b=document.forms["registration"]["address"].value;
var c=document.forms["registration"]["post"].value;
var d=document.forms["registration"]["email"].value;
var z=document.forms["registration"]["password"].value;
if (f==null || f=="")
{
document.forms["registration"]["FirstName"].focus();
alert("Please enter your first name");
return false;
}
if (a==null || a=="")
{
document.forms["registration"]["Surname"].focus();
alert("Please enter your surname");
return false;
}
if (b==null || b=="")
{
alert("Please enter your address");
document.forms["registration"]["address"].focus();
return false;
}
if (c==null || c=="")
{
alert("Please enter your postcode");
document.forms["registration"]["post"].focus();
return false;
}
if (d==null || d=="")
{
document.forms["registration"]["email"].focus();
alert("Please enter your email address");
return false;
}
else
{
var emailAddress = d;
var atLoc = emailAddress.indexOf("#",1);
var dotLoc = emailAddress.indexOf(".",atLoc+2);
var len = emailAddress.length;
if (atLoc > 0 && dotLoc > 0 && len > dotLoc+2)
{
return true;
}
else
{
alert("Invalid E-mail address format! Please enter your e-mail address again.");
document.forms["registration"]["email"].focus();
return false;
}
}
}
}
It no longer works...? Puzzled, any help appreciated.

nested if else in javascript

I have trouble with the nested if structure in javascript. Any help is appreciated.
function validateForm()
{
var a = document.forms["demo1"]["addr1"].value;
var b = document.forms["demo1"]["city"].value;
//var c = document.forms["demo1"]["fname"].value;
//var d = document.forms["demo1"]["lname"].value;
//var f = document.forms["demo1"]["phno"].value;
//var g = document.forms["demo1"]["email"].value;
//var g1 = document.forms["demo1"]["cemail"].value;
//var h = document.forms["demo1"]["pwd"].value;
//var h1 = document.forms["demo1"]["cpwd"].value;
if(b=="" || b==null)
{
alert("Please enter your city");
return false;
break;
}
else if(a=="" || a==null)
{
alert("Please enter your address");
return false;
break;
}
else {return true;}
}
<form name = "demo1" action = "exp2.php" onsubmit = "return validateForm()" method = "POST">
The code works fine(as intended) if there is only one if statement. But I am not getting the intended result if more than one if else is been deployed.
Regards,
Mani
First, you don't need break statements, they're useless in this context.
Second, you don't need to nest and, in fact, you shouldn't since checking of a and b is independent of each other:
if(b=="" || b==null)
{
alert("Please enter your city");
return false;
}
if(a=="" || a==null)
{
alert("Please enter your address");
return false;
}
return true;
What about shorten ur code with reusable isEmpty function
function validateForm()
{
var isEmpty = function ( name , label ){
var val = document.forms["demo1"][ name ].value;
if( ! val )
{
alert("Please enter your "+ label );
return true;
}
return false;
}
return !isEmpty( 'city', 'city') &&
!isEmpty( 'addr1', 'address');
}
isEmpty return true or false
if(b=="" || b==null) {
alert("Please enter your city");
return false;
}
else if(a=="" || a==null) {
alert("Please enter your address");
return false;
}
else {
return true;
}
Like paxdiablo says you can use two separate if statements.
But if you only want to require an address when a city is entered you must realize that this is not a nested if statement. This is:
if(b=="" || b==null)
{
alert("Please enter your city");
return false;
}
else
{
if(a=="" || a==null)
{
alert("Please enter your address");
return false;
}
else
{
return true;
}
}
A more reabable version would be, imo:
if(b=="" || b==null)
{
alert("Please enter your city");
return false;
}
if((b=="" || b == null) && (a=="" || a==null))
{
alert("Please enter your address");
return false;
}

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