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PHP高级特性二之文件处理

PHP中的文件处理也是一个相当重要的模块,这一篇的主要内容就是PHP中文件系统的简介。

文件系统用途

1. 项目处理都离不开文件处理

2. 可以用文件长时间保存数据

3. 建立缓存,在服务器中进行文件操作

文件系统函数用法详述

1.基本的判断函数

is_dir — 判断给定文件名是否是一个目录

is_file — 判断给定文件名是否为一个文件

is_executable — 判断给定文件名是否可执行

is_link — 判断给定文件名是否为一个符号连接

is_readable — 判断给定文件名是否可读

is_uploaded_file — 判断文件是否是通过 HTTP POST 上传的

is_writable — 判断给定的文件名是否可写

is_writeable — is_writable 的别名

2.文件相关信息获取

file_exists — 检查文件或目录是否存在

fileatime — 取得文件的上次访问时间

filectime — 取得文件的 inode 修改时间

filegroup — 取得文件的组

fileinode — 取得文件的 inode

filemtime — 取得文件修改时间

fileowner — 取得文件的所有者

fileperms — 取得文件的权限

filesize — 取得文件大小

filetype — 取得文件类型

下面我们写一个例子,传入文件名,打印它的详细信息。

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