如何在代码中添加上传文件格式

Question

我有问题。此代码只能上传图像，我也需要上传其他文件类型。 如何添加文件上传类型/格式以及如何添加文件上传大小限制？ 请帮我解决这个问题。

<?
if (!empty($_FILES['uploaded_file'])) {
    $path = "uploads/";
    $path = $path . basename( $_FILES['uploaded_file']['name']);

    if (move_uploaded_file($_FILES['uploaded_file']['tmp_name'], $path)) {
        echo "The file ".  basename( $_FILES['uploaded_file']['name']). 
            " has been uploaded";
    } else{
        echo "There was an error uploading the file, please try again!";
    }
}
?>