PHP Fall Though on Switch

PHP Fall Though on Switch

order matters, but handy sometimes:

 

 

function test($a) {

    switch ($a) {

 

   case 1 :

      echo '1';

     

    case 2 :

      echo '2';

      

    case 3 :

       echo '3';

       break;

 

}

 

}

 

test(2); // result 23

 
// Example to use fall through to get max file upload size
**
* This function returns the maximum files size that can be uploaded 
* in PHP
* @returns int File size in bytes
**/
function getMaximumFileUploadSize()  
{  
    return min(convertPHPSizeToBytes(ini_get('post_max_size')), convertPHPSizeToBytes(ini_get('upload_max_filesize')));  
}  
 
/**
* This function transforms the php.ini notation for numbers (like '2M') to an integer (2*1024*1024 in this case)
* 
* @param string $sSize
* @return integer The value in bytes
*/
function convertPHPSizeToBytes($sSize)
{
    //
    $sSuffix = strtoupper(substr($sSize, -1));
    if (!in_array($sSuffix,array('P','T','G','M','K'))){
        return (int)$sSize;  
    } 
$iValue = substr($sSize, 0, -1);
// Fall through order matters!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    switch ($sSuffix) {
        case 'P':
            $iValue *= 1024;
            // Fallthrough intended
        case 'T':
            $iValue *= 1024;
            // Fallthrough intended
        case 'G':
            $iValue *= 1024;
            // Fallthrough intended
        case 'M':
            $iValue *= 1024;
            // Fallthrough intended
        case 'K':
            $iValue *= 1024;
            break;
    }
    return (int)$iValue;
}      

Sources

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