函数:is_dir()
功能:判断给定文件名是否是一个目录
说明:
bool is_dir ( string $filename )
如果文件名存在并且为目录则返回 TRUE。
如果 filename 是一个相对路径,则按照当前工作目录检查其相对路径。
注: 本函数的结果会被缓存。更多信息参见 clearstatcache()。
例子1
<? var_dump(is_dir('a_file.txt')) . "\n"; var_dump(is_dir('bogus_dir/abc')) . "\n"; var_dump(is_dir('..')); //one dir up ?>
上例将输出:
bool(false)
bool(false)
bool(true)
例子2
<?php $file = "images"; if(is_dir($file)) { echo ("$file is a directory"); } else { echo ("$file is not a directory"); } ?>
输出:
如果存在images这个目录,则输出:
images is a directory
以上所述就是本文的全部内容了,希望大家能够喜欢。

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