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PHP isset problem

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Jun 21.2006

Hi, i have this:

[code=php]
if(!$book){
echo “book”
}
[/code]

But i get an error on this..like:
Notice: Undefined variable: book in /www/websites/maakeenseenboek.com/www.maakeenseenboek.com/index.php on line 83

what can i do about it i know what to do when it is a normal script like:

[code=php]
if($book){
echo “book”
}
[/code]

then i can solve it:

[code=php]
if(isset($book)){
echo “book”
}
[/code]

but what to do with the !

thanks in advance

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PHP

2 Comments(s) ↴

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@shane_carrJun 21.2006 — [code=php]
if(isset($book)){
echo "Book";
}else{
echo "No Book";
}

//or, if you just want to see if it's not set

if(!isset($book)){
echo "No Book";
}
[/code]
Copy linkTweet thisAlerts:
@NogDogJun 21.2006 — I think this might be what you're after...
[code=php]
if(empty($book) {
[/code]
...which is functionally equivalent to...
[code=php]
if(!isset($book) or !$book) {
[/code]
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