phpでファイルがアップロードされない場合の解析例と解決策

upload_max_filesize = 300M
post_max_size = 300M

php_value upload_max_filesize "300M"
php_value post_max_size "300M"

$error=$myfile['myfile']['error'];
  if ($error==0){//0, means the upload was successful
    if (move_uploaded_file($tmp,"userpic/". $picname)) {
      echo "Move file successfully";
    }else{
      echo "Failed to move file";
    }
  }else{//not 0, match error message
    switch ($error){
      case 1:
        echo "Maximum file upload limit exceeded";//upload_max_filesize in php.ini
        break;
      case 2:
        echo "Exceeded form file size limit";//MAX_FILE_SIZE option in HTML form
        break;
      case 3:
        echo "The file was partially uploaded";
        break;
      case 4:
        echo "No files selected for upload";
        break;
      case 7://file write failed
      case 8:
        echo "System error";
        break;
    }
  }

<! --form hidden field to limit upload size -->
<input type="hidden" name="MAX_FILE_SIZE" value="2097152">
<! --accept Restrictions on file types -->
<input type="file" name="myfile" accept="image/jpeg,image/png">

$size=$myfile['size'];//Get the file size
$MaxSize=2097152;//set the maximum allowed bytes
$type=$myfile['type'];//Get the image type
$AllowTypr=array('image/jpeg','image/png','image/gif');//allow type array
if ($error==0){//0, means the upload was successful
  if ($size>$MaxSize){
    echo "<script>alert('File size exceeded limit');</script>";
    echo "<script>history.back(1);</script>";
    exit();
  }
  if (!in_array($type,$AllowTypr)){
    echo "<script>alert('Please upload the correct image type');</script>";
    echo "<script>history.back(1);</script>";
    exit();
  }