如果 为空，则表示文件尚未上传。你应该看看为什么。$_FILES[$field]['tmp_name']$_FILES[$field]['error']
FWIW，据我所知，哑剧类型是由浏览器提供的。$_FILES[]
更新：这里有一些灌封的代码来处理所有文件上传错误：
$message = 'Error uploading file';
switch( $_FILES['newfile']['error'] ) {
case UPLOAD_ERR_OK:
$message = false;;
break;
case UPLOAD_ERR_INI_SIZE:
case UPLOAD_ERR_FORM_SIZE:
$message .= ' - file too large (limit of '.get_max_upload().' bytes).';
break;
case UPLOAD_ERR_PARTIAL:
$message .= ' - file upload was not completed.';
break;
case UPLOAD_ERR_NO_FILE:
$message .= ' - zero-length file uploaded.';
break;
default:
$message .= ' - internal error #'.$_FILES['newfile']['error'];
break;
}
if( !$message ) {
if( !is_uploaded_file($_FILES['newfile']['tmp_name']) ) {
$message = 'Error uploading file - unknown error.';
} else {
// Let's see if we can move the file...
$dest .= '/'.$this_file;
if( !move_uploaded_file($_FILES['newfile']['tmp_name'], $dest) ) { // No error supporession so we can see the underlying error.
$message = 'Error uploading file - could not save upload (this will probably be a permissions problem in '.$dest.')';
} else {
$message = 'File uploaded okay.';
}
}
}
