PHP值条件错误测试

Question

Is $var==1 the proper syntax for testing whether $var has a value?

I ask, because I'm getting a failure on a simple conditional.

Here's the code that seems to be failing:

if ($slcustom31==1) {$page="http://www.mydomain.com/members/page_Alpha.php";}

I assume that there's something wrong with the syntax, $var==1 .

++++++++ Here's the entire conditional, if that makes things clearer:

//condition 1
if ($slcustom31==1) {$page="http://www.mydomain.com/members/page_Alpha.php";} 

//condition2
elseif ($slcustom31!=1 AND $slcustom29!="") {$page="http://www.mydomain.com/members/".$slcustom29;}

//condition3
else {$page="http://www.mydomain.com/members/page_Beta.php";} 

sl_redirecttourl($page);

SPECIFIC SYMPTOM: Script ignores condition1 and condition2, defaults to condition3.

++++ And if it helps, here's the entire (short) script:

$groupswithaccess="somegroup";

require_once("../slpw/sitelokpw.php");
require_once("../slpw/sitelokapi.php"); //gets value being tested by conditional

if ($slcustom31==1) {$page="http://www.mydomain.com/members/page_Alpha.php";} 
elseif ($slcustom31!=1 AND $slcustom29!="") {$page="http://www.mydomain.com/members/".$slcustom29;}//not finished, but started
else {$page="http://www.mydomain.com/members/page_Beta.php";} 

sl_redirecttourl($page);

Can someone tell me what I should do differently?

Thanks!

Answer 1

if($var ==1){
//returns true only if var is 1
}

if(isset($var)){
//returns true if you currently have any value stored as the variable $var
}