duancenxie2233 2012-06-29 08:52
浏览 12
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if($ variable!='')澄清

if($hOne!='') {
   echo 'yes';
 } else {
   echo 'no';
}

SO for a while i have been using the above code to determine id X variable has been set, now this was working ok until working on a wordpress site (i wont go into too much details) but basically initially the varabile has never been touched and works as intended, if you enter a value and then delete that value it seems to think its been set.

a way i got round this is to use the below code, my question is, is there a better way to do this.

Cheers

if (preg_match('/[A-Za-z]/i', $hone)) {
       echo 'yes';
     } else {
       echo 'no';
    }

Result Used the below which works as intended, thank you all:

if(isset($hone) and
       !empty($hone)) {
        echo '1';
    } else {
        echo '2';
    }
  • 写回答

3条回答 默认 最新

  • dongxie5698 2012-06-29 08:56
    关注

    Right. My advice is to go back and read the PHP documentation. Make it a week or two project to get most sections at least glimpsed at.

    You want to use isset, or empty.

    if (isset($hOne)) { }
    

    will check if the variable exists,

    if (empty($hOne)) { }
    

    checks if it is set but empty.

    To help you learn PHP, I'd recommend sticking this at the top of your app:

    $test_server = $_SERVER['SERVER_NAME'] == "127.0.0.1" || $_SERVER['SERVER_NAME'] == "localhost" || substr($_SERVER['SERVER_NAME'],0,3) == "192"; 
    
    ini_set('display_errors',$test_server);
    ini_set('display_startup_errors',$test_server);
    
    error_reporting(E_ALL|E_STRICT);
    

    (Or if you are not working locally, just set $test_server to 1.)

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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