need JS form validation example

Hi everyone,
I want to be able to verify 2 fields in my website form:

• phone number: must be a 10 digit number;
• email address: must contain "@"

Please provide me with the easiest way to do this validation.

Thanks.

 

See Email validate
function checkEmail(email) {
if (email.length == 0) {
window.alert(“You must provide an e-mail address.”);
return false;
}
if (email.indexOf(“/”) > -1) {
window.alert(“E-mail address has invalid character: /”);
return false;
}
if (email.indexOf(“:”) > -1) {
window.alert(“E-mail address has invalid character: :”);
return false;
}
if (email.indexOf(“,”) > -1) {
window.alert(“E-mail address has invalid character: ,”);
return false;
}
if (email.indexOf(“;”) > -1) {
window.alert(“E-mail address has invalid character: ;”);
return false;
}
if (email.indexOf(“@”) < 0) {
window.alert(“E-mail address is missing @”);
return false;
}
if (email.indexOf(“\.”) < 0) {
window.alert(“E-mail address is missing .”);
return false;
}
return true;
}
More see http://www.developerzone.biz/index.php?option=com_content&task=view&id=137&Itemid=45

 

Here's a form validation
---------------
Javascript
---------------
// Some Routines for HTML-Form Validation

function trimXSpaces(Str){
if(!Str.length)
return Str;

while(Str.charAt(0) == ' ')
Str = Str.substring(1, Str.length);

if(!Str.length)
return Str;

while(Str.charAt(Str.length - 1) == ' ')
Str = Str.substring(0, Str.length - 1);

return Str;
}

function returnSelection(radioField)
{
var selection = null;
for (i=0; i < radioField.length; i++)
{
if (radioField.checked)
{
selection=radioField.value;
return selection;
}
}
return selection;
}

// Check if Field contains something
function ContainsSomething(Field)
{
if ((Field.type == "text") || (Field.type == "textarea") || (Field.type == "password") || (Field.type == "hidden"))
{
Str = trimXSpaces(Field.value);
if (Str == "")
{
return false;
}
}
else
{
if (returnSelection(Field) == null)
{
return false;
}
}

return true;
}

// Check for valid (ie containg "@", ".",
// and more than 6 characters) email-address in Field
function IsValidEmail(Field)
{
if (!ContainsSomething(Field))
{
return false;
}
if (Field.value.indexOf("@")==-1
|| Field.value.indexOf(".")==-1
|| trimXSpaces(Field.value).indexOf(" ")!=-1
|| Field.value.length<6)
{
return false;
}
else
{
return true;
}
}

// Check if Field contains a valid date of the form dd/mm/yy
function IsValidDate(Field)
{
if (!ContainsSomething(Field))
{
return false;
}
var indate=Field.value;
var sdate = indate.split("/")

var chkDate = new Date(Date.parse(indate))

var cmpDate = (chkDate.getMonth()+1)+
"/"+(chkDate.getDate())+
"/"+(chkDate.getYear())
var indate2 = (Math.abs(sdate[0]))+"/"+(
Math.abs(sdate[1]))+
"/"+(Math.abs(sdate[2]))
if (indate2 != cmpDate || cmpDate == "NaN/NaN/NaN")
{
return false
}
else
{
return true;
}
}

// Check if Field contains numeric data only
function IsNum(Field)
{
if (!ContainsSomething(Field))
{
return false;
}
theNum = parseFloat(Field.value);
if (Field.value != '' + theNum)
{
return false;
}
return true;
}

// Check if Field contains only letters
function IsOnlyLetters(Field)
{
if (!ContainsSomething(Field))
{
return false;
}
var Letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ��"
for (i=0; i < Field.value.length; i++)
{
var CheckChar = Field.value.charAt(i);
CheckChar = CheckChar.toUpperCase();
if (Letters.indexOf(CheckChar) == -1)
{
return false;
}
}
return true;
}

// Check if Field contains only digits in range Min to Max
function IsInRange(Field, Min, Max)
{
if (IsNum(Field) == false)
{
return false;
}
if (Field.value < Min || Max < Field.value)
{
return false;
}
return true;
}

// Check if Field is not equal to strCompare
function IsNotEqual(Field, strCompare)
{
if (Field.value== strCompare)
{
return false;
}
return true;
}
//compare two fields
function IsNotEqual2(Field, Field2)
{
if (Field.value == Field2.value)
{
return false;
}
return true;
}

function isCreditCard(st)
{
if (st.length > 19)
{
return (false);
}
sum = 0; mul = 1; l = st.length;
for (i = 0; i < l; i++)
{
digit = st.substring(l-i-1,l-i);
tproduct = parseInt(digit ,10)*mul;
if (tproduct >= 10)
{
sum += (tproduct % 10) + 1;
}
else
{
sum += tproduct;
}
if (mul == 1)
{
mul++;
}
else
{
mul--;
}
}
if ((sum % 10) == 0)
{
return (true);
}
else
{
return (false);
}
}

function IsVisa(cc)
{
if (((cc.length == 16) || (cc.length == 13)) && (cc.substring(0,1) == 4))
{
return isCreditCard(cc);
}
return false;
}
function IsMasterCard(cc)
{
firstdig = cc.substring(0,1);
seconddig = cc.substring(1,2);
if ((cc.length == 16) && (firstdig == 5) && ((seconddig >= 1) && (seconddig <= 5)))
{
return isCreditCard(cc);
}
return false;
}

function IsAmericanExpress(cc)
{
firstdig = cc.substring(0,1);
seconddig = cc.substring(1,2);
if ((cc.length == 15) && (firstdig == 3) && ((seconddig == 4) || (seconddig == 7)))
{
return isCreditCard(cc);
}
return false;
}

function IsValidCC(Field)
{
tempString = "";
bag = "- ";
for (i = 0; i < Field.value.length; i++)
{
var c = Field.value.charAt(i);
if (bag.indexOf(c) == -1) tempString += c;
}
cc = tempString;
if (!isCreditCard(cc))
{
return false;
}
if (!IsMasterCard(cc) && !IsVisa(cc) && !IsAmericanExpress(cc))
{
return false;
}
return true;
}

//added by je
// Check if Field contains only digits and does not start with 0 or 1
function IsValidIVR(Field)
{
if (IsNum(Field) == false)
{
return false;
}
if (Field.value.substring(0,1) == "0" || Field.value.substring(0,1) == "1")
{
return false;
}
return true;
}

function isInteger(inputVal) {

inputStr = inputVal.toString();

for (var i = 0; i < inputStr.length; i++) {
var oneChar = inputStr.charAt(i);
if (oneChar < "0" || oneChar > "9") {
if (i == 0 && oneChar == "-") {
continue;
}
return false;
}
}
return true;
}


// radio checker
function ValidateRadio(Field) {
myOption = -1;
for (i=Field.choice.length-1; i > -1; i--) {
if (Field.choice.checked) {
myOption = i;
}
}

if (myOption == -1)
return false;
else
return true;
}


-----------------------------------------------------------------------------
Sample code:
<script language="javascript" type="text/javascript">

function checkComplete(Form){

if(!ValidateRadio(Form)){
alert("Please Select a Choice.");
return false;
}

if(!ContainsSomething(Form.firstname)){
alert("First Name should not be blank.");
Form.firstname.focus();
return false;
}

if(!ContainsSomething(Form.lastname)){
alert("Last Name should not be blank.");
Form.lastname.focus();
return false;
}

if(!ContainsSomething(Form.uname)){
alert("Username should not be blank.");
Form.uname.focus();
return false;
}

if(!IsValidEmail(Form.email)){
alert("Email should not be blank or invalid.");
Form.email.focus();
return false;
}
}

</script>