How do I convert a JavaScript event handler inline in HTML to be parameterized?

Question

Quick JavaScript question. I am creating a simple script where a form field entry disappears/reappears using onfocus and onblur.

I'm wondering why the following inline script works:

<div>
<input type="text" name="email" id="email" value="Requires validation"
onfocus="if(this.value == 'Requires validation'){this.value = '';}"
onblur="formappear()">
</div>

and the following script with a parameterized function doesn't:

<head>
<script type='text/javascript'>
function formclear(field) {

if (field.value == "Requires validation") {
field.value = "";
}

}
</script>
</head>
<body>
<div>
<input type="text" name="email" id="email" value="Requires validation"
onfocus="formclear(this.id)" onblur="formappear()">
</div>
</body>

I appreciate any responses in advance, I'm sure it's a simple mistake I'm making.

tymeJV · Accepted Answer · 2013-05-28 17:22:02Z

1

Dont pass in this.id, just pass in this

<input type="text" name="email" id="email" value="Requires validation" onfocus="formclear(this)" onblur="formappear()">

Demo: http://jsfiddle.net/se6wm/

You were passing in the id of the input, so when you were using field.value it was actually trying to do email.value which doesn't exist.

answered May 28, 2013 at 17:22

tymeJV

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1 Comment

Pete_1 Over a year ago

Thanks for the responses, dumb mistake, but I'm always learning. I'll accept the answer when I'm able to.

eidsonator · Accepted Answer · 2013-05-28 17:22:10Z

0

Because you are passing in the id instead of the this

answered May 28, 2013 at 17:22

eidsonator

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Comments

Tamil Selvan C · Accepted Answer · 2014-04-04 16:45:50Z

0

pass a value as formclear(this) instead of formclear(this.id)

<input type="text" name="email" id="email" value="Requires validation"
onfocus="formclear(this)" onblur="formappear()">

edited Apr 4, 2014 at 16:45

answered May 28, 2013 at 17:23

Tamil Selvan C

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