Help with form validation - textarea

julescode · 02-17-2013, 03:55 PM

Hi All
I am new to Javascript and am unable to get the validation to work for the text area or comments section of my form. I got it to work for the regular text fields but for some reason it doesn't work for the text area. I also need to validate the rating area. I appreciate your help!!

Here's what I tried first:

<script type="text/javascript">

function validateForm()

{
if (document.forms[0].comments.value == "" )
{
alert("Please enter your comments.");
form[0].comments.focus();
return false;

} // end if
return true;
}

// end function validateForm

</script>

Then I did some research and found this other method. Here's the entire file:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">

<head>

<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>

<title>Julie Mazza Web Form</title>
<link rel="stylesheet" type="text/css" href="styles.css" />

<script type="text/javascript">

function validateForm()

{
var comments = document.getElementById("comments");

if ($.trim(comments.value) == '') {
alert("Please Write Your Comments");
return false;
} else {
return true;
}
}

</script>

</head>

<body>

<div id="wrapper">
<div id="header"></div>

<h1>Sample Feedback Form</h1>

<form method="post" action="index.xhtml" onsubmit="return validateForm()" >
<fieldset>

<label>First Name:<input type="text" name="firstname" id="firstname" /></label>
<br /> <br />
<label> Last Name:<input type="text" name="lastname" id="lastname" /></label>
<br /> <br />
<label>Street Address:<input type="text" name="stradd" id="stradd" /></label>
<br /> <br />
<label>City:<input type="text" name="city" id="city" /></label>
<br /> <br />
<label>State:<input type="text" name="state" id="state" /></label>
<br /> <br />
<label>Zip:<input type="text" name="zip" id="zip" /></label>
<br /> <br />
<label>Country:<input type="text" name="Country" id="Country" /></label>
<br /> <br />
<label>Your email:<input type="text" name="FromAddress" id="FromAddress" /></label>
<br /> <br />
</fieldset>

<fieldset>

Your Comments:<textarea name="comments" id="comments" cols="40" rows="2" >
Enter your comments here </textarea>

<br /> <br />
</fieldset>

<fieldset>
Rate this site<br />
<input type="radio" name="rating" id="rating5" value="5" /> 5 - Excellent <br />
<input type="radio" name="rating" id="rating4" value="4" /> 4 - Very Good <br />
<input type="radio" name="rating" id="rating3" value="3" /> 3 - Average <br />
<input type="radio" name="rating" id="rating2" value="2" /> 2 - Below Average <br />
<input type="radio" name="rating" id="rating1" value="1" /> 1 - Poor <br />
</fieldset>

<p>
<input type="hidden" name="ToAddress" value="jmazza3@nycap.rr.com" />
<input type="hidden" name="CCAddress" value="" />
<input type="hidden" name="Subject" value="WSD: Assignment 2.2 - Web Form for Julie Mazza" />
</p>

<fieldset>

<input type="reset" value="Reset" />

<input type="submit" value="Submit" />

</fieldset>

</form>

</div>
</body>

</html>

Philip M · 02-17-2013, 07:10 PM

Try this:-

Code:

<form id = "myform" onsubmit = "return validateTA()">
Your Comments:<textarea name="comments" id="comments" cols="40" rows="2" onfocus = "this.value = '' " onblur = "return validateTA()" >
Enter your comments here </textarea>
<br><br>
<input type = "submit" value = "Submit The Form">

</form>

<script type="text/javascript">

function validateTA() {
var val = document.getElementById("comments").value;  // Do not use the same word for an HTML element name/id and a Javascript variable
val = val.replace(/^\s+|\s+$/g,"");  // strip leading and trailing spaces
val = val.replace(/[^0-9a-z\s\.,;?!]/gi, "");  // strip unwanted special characters, ^ means NOT, adjust to suit
val = val.replace(/\s{2,}/g," ");  // replace multiple spaces with one space
document.getElementById("comments").value = val;   // write it back to the field
if (val.length < 8) {  // set a minimum number of characters
alert ("Please enter your comments - using a minimum of 8 characters"); // alerts are regarded as obsolete and should be used only for testing purposes.  Use DOM methods to display a message to the user.
document.getElementById("comments").focus();
return false;
}
return true;
}

</script>

Be aware that form validation of the pattern if (document.formname.formfield.value == "") - that is blank - is barely worthy of the name, and virtually useless, as even a single space, an X or a ? will return false, that is pass the validation. A proper name may only contain letters, hyphen, space and apostrophe.
Numeric values, such as zip codes, phone numbers and dates, should be validated as such. Ditto email addresses. This topic has been covered many times before in this forum.

Three is no trim() function built into Javascript - $trim() is jQuery.

Why should I do anything for posterity? What has posterity ever done for me?
Groucho Marx (1890 - 1977)

felgall · 02-17-2013, 08:52 PM

Quote:

Originally Posted by Philip M

Three is no trim() function built into Javascript - $trim() is jQuery.

The latest version of JavaScript does have a trim method for Strings.

https://developer.mozilla.org/en-US/...ts/String/Trim

Even Internet Explorer supports it in the latest version of the browser - http://msdn.microsoft.com/en-us/libr...(v=vs.94).aspx

Old Pedant · 02-17-2013, 11:20 PM

Actually, the original code *WILL* work:

Code:

function validateForm()
{
    if (document.forms[0].comments.value == "" )
    {
        alert("Please enter your comments.");
        form[0].comments.focus();
        return false;
    } // end if
    return true;
}

But *ONLY* if you code the textarea thus:

Code:

    <textarea name="comments"></textarea>

That is. all on one line.

When you code it thus:

Code:

    <textarea name="comments">
    </textarea>

Then it *ALREADY* contains a line break character (and, if the </textarea> is not at the very start of the line, it will contain spaces)!! And so of course it will never be equal to "".

*******

I disagree with one part of Philip's advice:

Code:

val = val.replace(/\s{2,}/g," ");  // replace multiple spaces with one space

The problem with that is that \s does *NOT* mean "space"! It means "whitespace".

So that code would also replace, for example, two line breaks with a single space!

And, in <textarea>s, line breaks usually *are* considered significant and should not be changed.

On top of that, many people like to type extra spaces into text areas to improve readability of their message. So I'd just omit that line completely.

But if you must use it, then don't use \s. Just use:

Code:

val = val.replace(/ {2,}/g," ");  // there is a space before the {

Philip M · 02-18-2013, 08:15 AM

Quote:

Originally Posted by Old Pedant

And, in <textarea>s, line breaks usually *are* considered significant and should not be changed.

On top of that, many people like to type extra spaces into text areas to improve readability of their message. So I'd just omit that line completely.

But if you must use it, then don't use \s. Just use:

Code:

val = val.replace(/ {2,}/g," ");  // there is a space before the {

Good point!

But I would have thought that we want to block "a (many spaces) b" which would otherwise be of sufficient length.

Philip M · 02-18-2013, 08:17 AM

Quote:

Originally Posted by felgall

The latest version of JavaScript does have a trim method for Strings.

https://developer.mozilla.org/en-US/...ts/String/Trim

Even Internet Explorer supports it in the latest version of the browser - http://msdn.microsoft.com/en-us/libr...(v=vs.94).aspx

I know, but that is IE10

but as Old Pedant points out, there are still plenty of people using IE5.5. And val = val.replace(/^\s+|\s+$/g,""); seems to be hardly any longer.

I am afraid that I have this eccentric idea that I need to continue support for elderly (but still extant) browsers.

The trim() method states "The characters that are removed include space, tab, form feed, carriage return, and line feed." In other words, whitespace. That was Old Pedant's point! In a textarea newlines may be significant.