Mengatur File Size Upload File di PHP

function untuk mengatur besar file yang di perbolehkan di upload dengan PHP
contoh

 <?php  
 function display_filesize($filesize){  
   if(is_numeric($filesize)){  
   $decr = 1024; $step = 0;  
   $prefix = array('Byte','KB','MB','GB','TB','PB');  
   while(($filesize / $decr) > 0.9){  
     $filesize = $filesize / $decr;  
     $step++;  
   }   
   return round($filesize,2).' '.$prefix[$step];  
   } else {  
   return 'NaN';  
   }  
 }  
 ?>  

Upload Multiple Files Menggunakan PHP Function

function upload multiple file menggunakan PHP

contoh:

 <?php  
 header('Content-Type: text/plain; charset=utf-8');  
 try {  
   // Undefined | Multiple Files | $_FILES Corruption Attack  
   // If this request falls under any of them, treat it invalid.  
   if (  
     !isset($_FILES['upfile']['error']) ||  
     is_array($_FILES['upfile']['error'])  
   ) {  
     throw new RuntimeException('Invalid parameters.');  
   }  
   // Check $_FILES['upfile']['error'] value.  
   switch ($_FILES['upfile']['error']) {  
     case UPLOAD_ERR_OK:  
       break;  
     case UPLOAD_ERR_NO_FILE:  
       throw new RuntimeException('No file sent.');  
     case UPLOAD_ERR_INI_SIZE:  
     case UPLOAD_ERR_FORM_SIZE:  
       throw new RuntimeException('Exceeded filesize limit.');  
     default:  
       throw new RuntimeException('Unknown errors.');  
   }  
   // You should also check filesize here.   
   if ($_FILES['upfile']['size'] > 1000000) {  
     throw new RuntimeException('Exceeded filesize limit.');  
   }  
   // DO NOT TRUST $_FILES['upfile']['mime'] VALUE !!  
   // Check MIME Type by yourself.  
   $finfo = new finfo(FILEINFO_MIME_TYPE);  
   if (false === $ext = array_search(  
     $finfo->file($_FILES['upfile']['tmp_name']),  
     array(  
       'jpg' => 'image/jpeg',  
       'png' => 'image/png',  
       'gif' => 'image/gif',  
     ),  
     true  
   )) {  
     throw new RuntimeException('Invalid file format.');  
   }  
   // You should name it uniquely.  
   // DO NOT USE $_FILES['upfile']['name'] WITHOUT ANY VALIDATION !!  
   // On this example, obtain safe unique name from its binary data.  
   if (!move_uploaded_file(  
     $_FILES['upfile']['tmp_name'],  
     sprintf('./uploads/%s.%s',  
       sha1_file($_FILES['upfile']['tmp_name']),  
       $ext  
     )  
   )) {  
     throw new RuntimeException('Failed to move uploaded file.');  
   }  
   echo 'File is uploaded successfully.';  
 } catch (RuntimeException $e) {  
   echo $e->getMessage();  
 }  
 ?>