[thelist] JavaScript: A Confusion
Scott Brady
evolt at scottbrady.net
Tue Feb 26 15:30:01 CST 2002
The "!" operator means "not".
It's most often used in conditionals and function returns.
let's say you have a function, called "isValidEmail(theString)" which checks
to see if the given string is a valid e-mail address. If it is, it returns
true. if not, it returns false.
You want to alert the user if the e-mail address they entered in the textbox
"email" in the form called "form1" is NOT valid, so you'd do:
if (!isValidEmail(document.form1.email))
{
alert('That e-mail address is not valid.');
return false;
}
Does that make sense?
Scott
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Scott Brady
http://www.scottbrady.net/
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