JavaScript Form Validation
JavaScript can be used to validate input data in HTML forms before
sending off the content to a server.
JavaScript Form Validation
JavaScript can be used to validate input data in HTML forms before sending off the
content to a server.
Form data that typically are checked by a JavaScript could be:
- has the user left required fields empty?
- has the user entered a valid e-mail address?
- has the user entered a valid date?
- has the user entered text in a numeric field?
Required Fields
The function below checks if a required field has been left empty. If the
required field is blank, an alert box alerts a message and the function returns
false. If a value is entered, the function returns true
(means that data is OK):
function validate_required(field,alerttxt)
{
with (field)
{
if (value==null||value=="")
{
alert(alerttxt);return false;
}
else
{
return true;
}
}
}
|
The entire script, with the HTML form could look something like this:
<html>
<head>
<script type="text/javascript">
function validate_required(field,alerttxt)
{
with (field)
{
if (value==null||value=="")
{alert(alerttxt);return false;}
else {return true}
}
}
function validate_form(thisform)
{
with (thisform)
{
if (validate_required(email,"Email must be filled out!")==false)
{email.focus();return false;}
}
}
</script>
</head>
<body>
<form action="submitpage.htm"
onsubmit="return validate_form(this)"
method="post">
Email: <input type="text" name="email" size="30">
<input type="submit" value="Submit">
</form>
</body>
</html>
|
E-mail Validation
The function below checks if the content has the general syntax of an email.
This means that the input data must contain at least an @ sign and a dot (.).
Also, the @ must not be the first character of the email address, and the last
dot must at least be one character after the @ sign:
function validate_email(field,alerttxt)
{
with (field)
{
apos=value.indexOf("@");
dotpos=value.lastIndexOf(".");
if (apos<1||dotpos-apos<2)
{alert(alerttxt);return false;}
else {return true;}
}
}
|
The entire script, with the HTML form could look something like this:
<html>
<head>
<script type="text/javascript">
function validate_email(field,alerttxt)
{
with (field)
{
apos=value.indexOf("@");
dotpos=value.lastIndexOf(".");
if (apos<1||dotpos-apos<2)
{alert(alerttxt);return false;}
else {return true;}
}
}
function validate_form(thisform)
{
with (thisform)
{
if (validate_email(email,"Not a valid e-mail address!")==false)
{email.focus();return false;}
}
}
</script>
</head>
<body>
<form action="submitpage.htm"
onsubmit="return validate_form(this);"
method="post">
Email: <input type="text" name="email" size="30">
<input type="submit" value="Submit">
</form>
</body>
</html>
|
The Ektron Intranet
lets you do everything you need to do on your corporate intranet and everything you want to do... all with just one application.
What can you do with the Ektron Intranet? |
|
Navigate through content, documents, assets, colleagues and workgroups quickly and intuitively with enterprise search |
|
Communicate with friends and colleagues with forums, message boards and corporate blogging using the new Social Networking Platform |
|
Promote collaboration among coworkers in your organization through project workspaces where others can efficiently find information and work together |
|
Personalize your company profile by bookmarking and organizing favorite content, uploading assets, posting photos, blogging, and more |
|
Interact with features like tagging, flagging, wikis and ratings found in the Web 2.0 Toolbox |
 |
Author/edit content, manage navigation, menus, audit trails, workflow and approvals with the best in breed Content Management |
|
|
|
|
See why there are 20,000+ Ektron integrations worldwide.
Request an
INSTANT DEMO or download a
FREE TRIAL today. |
|
HOME
Printer friendly page
