php - 如何获取上传文件的文件扩展名

Question

如何获取上传文件的文件类型？如果是.ppt,.docx,.pdf,.png,.mp4 > 等。有人可以帮我解决这个问题吗？我开始学习文件上传。请给我一些线索。只是 php 的新手。

这是我的代码。

<?php
include_once 'dbconfig.php';
if(isset($_POST['btn-upload']))
{    

    $file = rand(1000,100000)."-".$_FILES['file']['name'];
    $file_loc = $_FILES['file']['tmp_name'];
    $file_size = $_FILES['file']['size'];
    $folder="uploads/";

    // new file size in KB
    $new_size = $file_size/1024;  
    // new file size in KB

    // make file name in lower case
    $new_file_name = strtolower($file);
    // make file name in lower case

    $final_file=str_replace(' ','-',$new_file_name);

    if(move_uploaded_file($file_loc,$folder.$final_file))
    {
        $sql="INSERT INTO tbl_uploads(file,size) VALUES('$final_file','$new_size')";
        mysql_query($sql);
        ?>
        <script>
        alert('successfully uploaded');
        window.location.href='index.php?success';
        </script>
        <?php
    }
    else
    {
        ?>
        <script>
        alert('error while uploading file');
        window.location.href='index.php?fail';
        </script>
        <?php
    }
}
?>

Answer 1

试试这个:

$extension = pathinfo($_FILES['file']['name'], PATHINFO_EXTENSION);